diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8e550430..8384b9ce 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -63,6 +63,8 @@ if(DETHRACE_WERROR)
     endif()
 endif()
 
+option(DETHRACE_FIX_BUGS "Fix Dethrace bugs" ON)
+
 add_subdirectory(src/harness)
 add_subdirectory(src/S3)
 add_subdirectory(src/BRSRC13)
diff --git a/src/BRSRC13/CORE/V1DB/prepmesh.c b/src/BRSRC13/CORE/V1DB/prepmesh.c
index ddd68c39..948b048a 100644
--- a/src/BRSRC13/CORE/V1DB/prepmesh.c
+++ b/src/BRSRC13/CORE/V1DB/prepmesh.c
@@ -604,8 +604,8 @@ void BrModelUpdate(br_model* model, br_uint_16 flags) {
     if (model->flags & BR_MODF_PREPREPARED) {
         return;
     }
-    if (!model->faces || !model->vertices) {
-        BrFailure("BrModelUpdate: model has no faces or vertices (%s)", model->identifier ? model->identifier : "<NULL>");
+    if (model->faces == NULL || model->vertices == NULL) {
+        BrFailure("BrModelUpdate: model has no faces or vertices (%s)", model->identifier != NULL ? model->identifier : "<NULL>");
     }
     if (flags & BR_MODU_UNKNOWN) {
         flags |= BR_MODU_NORMALS;
diff --git a/src/DETHRACE/CMakeLists.txt b/src/DETHRACE/CMakeLists.txt
index 663b376c..47a9ee1a 100644
--- a/src/DETHRACE/CMakeLists.txt
+++ b/src/DETHRACE/CMakeLists.txt
@@ -1,8 +1,6 @@
 # Create object files so we can link them into the main binary and into tests without building twice.
 add_library(dethrace_obj OBJECT)
 
-option(DETHRACE_FIX_BUGS "Fix Dethrace bugs" ON)
-
 target_include_directories(dethrace_obj
     PUBLIC
         ${CMAKE_CURRENT_SOURCE_DIR}
@@ -35,7 +33,7 @@ else()
         -Wno-format-overflow
     )
 endif()
-if(BRENDER_FIX_BUGS)
+if(DETHRACE_FIX_BUGS)
     target_compile_definitions(dethrace_obj PRIVATE DETHRACE_FIX_BUGS)
 endif()
 
diff --git a/src/DETHRACE/common/car.c b/src/DETHRACE/common/car.c
index db1f6a4a..ef4c550d 100644
--- a/src/DETHRACE/common/car.c
+++ b/src/DETHRACE/common/car.c
@@ -1276,7 +1276,64 @@ void TestAutoSpecialVolume(tCollision_info* pCar) {
     int i;
     LOG_TRACE("(%p)", pCar);
 
-    STUB_ONCE();
+    mat = &pCar->car_master_actor->t.t.mat;
+    highest_p = 0.f;
+    for (i = 0; i < 3; i++) {
+        highest_p += BrVector3Dot((br_vector3*)mat->m[i], &pCar->water_normal) * pCar->bounds[0].min.v[i];
+    }
+    highest_p += BrVector3Dot((br_vector3*)mat->m[3], &pCar->water_normal) / WORLD_SCALE;
+    lowest_p = highest_p;
+    for (i = 0; i < 3; i++) {
+        val = (pCar->bounds[0].max.v[i] - pCar->bounds[0].min.v[i]) * BrVector3Dot((br_vector3*)mat->m[i], &pCar->water_normal);
+        if (val >= 0.f) {
+            highest_p += val;
+        } else {
+            lowest_p += val;
+        }
+    }
+
+    if (pCar->water_d > lowest_p) {
+        if (pCar->water_d >= highest_p) {
+            pCar->water_depth_factor = 1.f;
+        } else {
+            pCar->water_depth_factor = (pCar->water_d - lowest_p) / (highest_p - lowest_p);
+        }
+        if (pCar->auto_special_volume == NULL) {
+            vol = GetDefaultSpecialVolumeForWater();
+            if (vol == NULL) {
+                pCar->water_depth_factor = 1.f;
+                pCar->auto_special_volume = NULL;
+            } else {
+                BrVector3Scale(&tv, &pCar->bounds[0].min, WORLD_SCALE);
+                BrMatrix34ApplyP(&lp, &tv, mat);
+                BrVector3InvScale(&lp, &lp, WORLD_SCALE);
+                BrVector3Copy(&hp, &lp);
+                for (i = 0; i < 3; i++) {
+                    val = pCar->bounds[0].max.v[i] - pCar->bounds[0].min.v[i];
+                    BrVector3Scale(&tv, (br_vector3*)mat->m[i], val);
+                    if (BrVector3Dot(&pCar->water_normal, &tv) > 0.f) {
+                        BrVector3Accumulate(&hp, &tv);
+                    } else {
+                        BrVector3Accumulate(&lp, &tv);
+                    }
+                }
+                BrVector3Sub(&dir, &hp, &lp);
+                DisablePlingMaterials();
+                FindFloorInBoxBU(&lp, &dir, &tv, &d, pCar);
+                EnablePlingMaterials();
+                FindFloorInBoxBU(&pos, &dir, &tv, &d2, pCar);
+                if (d2 <= d) {
+                    pCar->water_depth_factor = 1.f;
+                    pCar->auto_special_volume = NULL;
+                } else {
+                    pCar->auto_special_volume = vol;
+                }
+            }
+        }
+    } else {
+        pCar->auto_special_volume = NULL;
+        pCar->water_depth_factor = 1.f;
+    }
 }
 
 // IDA: void __usercall MoveAndCollideCar(tCar_spec *car@<EAX>, br_scalar dt)
@@ -3765,222 +3822,113 @@ int AddEdgeCollPoints(br_vector3* p1, br_vector3* p2, br_bounds* pB, br_matrix34
     float scale;
 
     plane1 = LineBoxColl(p1, p2, pB, &hp1);
-    if (!plane1) {
+    if (plane1 == 0) {
         return 0;
     }
     if (n + 2 > pMax_pnts) {
         return 0;
     }
     plane2 = LineBoxColl(p2, p1, pB, &hp2);
-    if (!plane2) {
+    if (plane2 == 0) {
         return 0;
     }
-    if (plane1 == 8 || plane2 == 8 || (plane1 ^ plane2) != 4) {
-        if (plane1 != 8 || plane2 == 8) {
-            if (plane2 != 8 || plane1 == 8) {
-                if (plane1 == 8 || plane2 == 8) {
-                    if (plane1 == 8 && plane2 == 8) {
-                        BrMatrix34ApplyP(&op1, p1, pMold);
-                        plane3 = LineBoxColl(&op1, p1, pB, &pPoint_list[n]);
-                        GetPlaneNormal(&pNorm_list[n], plane3);
-                        d = n + (plane3 != 8);
-                        BrMatrix34ApplyP(&op1, p2, pMold);
-                        plane3 = LineBoxColl(&op1, p2, pB, &pPoint_list[d]);
-                        GetPlaneNormal(&pNorm_list[d], plane3);
-                        return (n != d) + (plane3 != 8);
-                    } else {
-                        return 0;
-                    }
-                } else {
-                    op1.v[0] = hp2.v[0] + hp1.v[0];
-                    op1.v[1] = hp2.v[1] + hp1.v[1];
-                    op1.v[2] = hp2.v[2] + hp1.v[2];
-                    op1.v[0] = op1.v[0] * 0.5;
-                    op1.v[1] = op1.v[1] * 0.5;
-                    op1.v[2] = op1.v[2] * 0.5;
-                    BrMatrix34ApplyP(&op2, &op1, pMold);
-                    plane3 = LineBoxColl(&op2, &op1, pB, &hp3);
-                    if (plane3 != 8 && plane3) {
-                        if (plane1 == plane3 || plane2 == plane3) {
-                            GetBoundsEdge(
-                                &pPoint_list[n],
-                                &edge,
-                                pB,
-                                plane1,
-                                plane2,
-                                &op2,
-                                &hp1,
-                                &hp2,
-                                c->collision_flag);
-                            op1.v[0] = hp1.v[0] - hp2.v[0];
-                            op1.v[1] = hp1.v[1] - hp2.v[1];
-                            op1.v[2] = hp1.v[2] - hp2.v[2];
-                            op2.v[0] = edge.v[1] * op1.v[2] - op1.v[1] * edge.v[2];
-                            op2.v[1] = edge.v[2] * op1.v[0] - op1.v[2] * edge.v[0];
-                            op2.v[2] = op1.v[1] * edge.v[0] - edge.v[1] * op1.v[0];
-                            scale = sqrt(op2.v[1] * op2.v[1] + op2.v[2] * op2.v[2] + op2.v[0] * op2.v[0]);
-                            if (scale <= 2.3841858e-7) {
-                                pNorm_list[n].v[0] = 1.0;
-                                pNorm_list[n].v[1] = 0.0;
-                                pNorm_list[n].v[2] = 0.0;
-                            } else {
-                                scale = 1.0 / scale;
-                                pNorm_list[n].v[0] = op2.v[0] * scale;
-                                pNorm_list[n].v[1] = op2.v[1] * scale;
-                                pNorm_list[n].v[2] = op2.v[2] * scale;
-                            }
-                            op1.v[0] = pB->max.v[0] + pB->min.v[0];
-                            op1.v[1] = pB->min.v[1] + pB->max.v[1];
-                            op1.v[2] = pB->max.v[2] + pB->min.v[2];
-                            op1.v[0] = op1.v[0] * 0.5;
-                            op1.v[1] = op1.v[1] * 0.5;
-                            op1.v[2] = op1.v[2] * 0.5;
-                            op1.v[0] = pPoint_list[n].v[0] - op1.v[0];
-                            op1.v[1] = pPoint_list[n].v[1] - op1.v[1];
-                            op1.v[2] = pPoint_list[n].v[2] - op1.v[2];
-                            if (pNorm_list[n].v[1] * op1.v[1] + pNorm_list[n].v[2] * op1.v[2] + pNorm_list[n].v[0] * op1.v[0] > 0.0) {
-                                pNorm_list[n].v[0] = -pNorm_list[n].v[0];
-                                pNorm_list[n].v[1] = -pNorm_list[n].v[1];
-                                pNorm_list[n].v[2] = -pNorm_list[n].v[2];
-                            }
-                            op1 = pNorm_list[n];
-                            BrMatrix34ApplyV(&pNorm_list[n], &op1, pMold);
-                            return 1;
-                        } else {
-                            GetBoundsEdge(
-                                &pPoint_list[n],
-                                &edge,
-                                pB,
-                                plane1,
-                                plane3,
-                                &hp3,
-                                &hp1,
-                                &hp2,
-                                c->collision_flag);
-                            GetBoundsEdge(
-                                &pPoint_list[n + 1],
-                                &edge,
-                                pB,
-                                plane2,
-                                plane3,
-                                &hp3,
-                                &hp1,
-                                &hp2,
-                                c->collision_flag);
-                            GetPlaneNormal(&pNorm_list[n], plane3);
-                            pNorm_list[n + 1] = pNorm_list[n];
-                            return 2;
-                        }
-                    } else {
-                        return 0;
-                    }
-                }
-            } else {
-                BrMatrix34ApplyP(&b, p2, pMold);
-                plane3 = LineBoxColl(&b, p2, pB, &hp3);
-                if (plane3 == 8) {
-                    return 0;
-                } else {
-                    pPoint_list[n] = hp3;
-                    GetPlaneNormal(&pNorm_list[n], plane1);
-                    if (plane1 == plane3 || (plane3 ^ plane1) == 4) {
-                        return 1;
-                    } else {
-                        GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane1, plane3, p2, &hp1, &hp3, c->collision_flag);
-                        op1.v[0] = p1->v[0] - p2->v[0];
-                        op1.v[1] = p1->v[1] - p2->v[1];
-                        op1.v[2] = p1->v[2] - p2->v[2];
-                        pNorm_list[n + 1].v[0] = edge.v[1] * op1.v[2] - op1.v[1] * edge.v[2];
-                        pNorm_list[n + 1].v[1] = edge.v[2] * op1.v[0] - op1.v[2] * edge.v[0];
-                        pNorm_list[n + 1].v[2] = op1.v[1] * edge.v[0] - edge.v[1] * op1.v[0];
-                        scale = sqrt(
-                            pNorm_list[n + 1].v[0] * pNorm_list[n + 1].v[0]
-                            + pNorm_list[n + 1].v[1] * pNorm_list[n + 1].v[1]
-                            + pNorm_list[n + 1].v[2] * pNorm_list[n + 1].v[2]);
-                        if (scale <= 2.3841858e-7) {
-                            pNorm_list[n + 1].v[0] = 1.0;
-                            pNorm_list[n + 1].v[1] = 0.0;
-                            pNorm_list[n + 1].v[2] = 0.0;
-                        } else {
-                            scale = 1.0 / scale;
-                            pNorm_list[n + 1].v[0] = pNorm_list[n + 1].v[0] * scale;
-                            pNorm_list[n + 1].v[1] = pNorm_list[n + 1].v[1] * scale;
-                            pNorm_list[n + 1].v[2] = pNorm_list[n + 1].v[2] * scale;
-                        }
-                        d = (plane1 - 1) & 3;
-                        if ((pNorm_list[n + 1].v[d] < 0.0) == (plane1 & 4) >> 2) {
-                            pNorm_list[n + 1].v[0] = -pNorm_list[n + 1].v[0];
-                            pNorm_list[n + 1].v[1] = -pNorm_list[n + 1].v[1];
-                            pNorm_list[n + 1].v[2] = -pNorm_list[n + 1].v[2];
-                        }
-                        op1 = pNorm_list[n + 1];
-                        BrMatrix34ApplyV(&pNorm_list[n + 1], &op1, pMold);
-                        return 2;
-                    }
-                }
-            }
-        } else {
-            BrMatrix34ApplyP(&a, p1, pMold);
-            plane3 = LineBoxColl(&a, p1, pB, &hp3);
-            if (plane3 == 8) {
-                return 0;
-            } else {
-                pPoint_list[n] = hp3;
-                GetPlaneNormal(&pNorm_list[n], plane2);
-                if (plane2 == plane3 || (plane3 ^ plane2) == 4) {
-                    return 1;
-                } else {
-                    GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane2, plane3, p1, &hp2, &hp3, c->collision_flag);
-                    op1.v[0] = p1->v[0] - p2->v[0];
-                    op1.v[1] = p1->v[1] - p2->v[1];
-                    op1.v[2] = p1->v[2] - p2->v[2];
-                    pNorm_list[n + 1].v[0] = edge.v[1] * op1.v[2] - op1.v[1] * edge.v[2];
-                    pNorm_list[n + 1].v[1] = edge.v[2] * op1.v[0] - op1.v[2] * edge.v[0];
-                    pNorm_list[n + 1].v[2] = op1.v[1] * edge.v[0] - edge.v[1] * op1.v[0];
-                    scale = sqrt(
-                        pNorm_list[n + 1].v[0] * pNorm_list[n + 1].v[0]
-                        + pNorm_list[n + 1].v[1] * pNorm_list[n + 1].v[1]
-                        + pNorm_list[n + 1].v[2] * pNorm_list[n + 1].v[2]);
-                    if (scale <= 2.3841858e-7) {
-                        pNorm_list[n + 1].v[0] = 1.0;
-                        pNorm_list[n + 1].v[1] = 0.0;
-                        pNorm_list[n + 1].v[2] = 0.0;
-                    } else {
-                        scale = 1.0 / scale;
-                        pNorm_list[n + 1].v[0] = pNorm_list[n + 1].v[0] * scale;
-                        pNorm_list[n + 1].v[1] = pNorm_list[n + 1].v[1] * scale;
-                        pNorm_list[n + 1].v[2] = pNorm_list[n + 1].v[2] * scale;
-                    }
-                    d = (plane2 - 1) & 3;
-                    if ((pNorm_list[n + 1].v[d] < 0.0) == (plane2 & 4) >> 2) {
-                        pNorm_list[n + 1].v[0] = -pNorm_list[n + 1].v[0];
-                        pNorm_list[n + 1].v[1] = -pNorm_list[n + 1].v[1];
-                        pNorm_list[n + 1].v[2] = -pNorm_list[n + 1].v[2];
-                    }
-                    op1 = pNorm_list[n + 1];
-                    BrMatrix34ApplyV(&pNorm_list[n + 1], &op1, pMold);
-                    return 2;
-                }
-            }
-        }
-    } else {
-        op1.v[0] = hp2.v[0] + hp1.v[0];
-        op1.v[1] = hp2.v[1] + hp1.v[1];
-        op1.v[2] = hp2.v[2] + hp1.v[2];
-        op1.v[0] = op1.v[0] * 0.5;
-        op1.v[1] = op1.v[1] * 0.5;
-        op1.v[2] = op1.v[2] * 0.5;
+    if (plane1 != 8 && plane2 != 8 && (plane1 ^ plane2) == 4) {
+        BrVector3Add(&op1, &hp2, &hp1);
+        BrVector3Scale(&op1, &op1, .5f);
         BrMatrix34ApplyP(&op2, &op1, pMold);
         plane3 = LineBoxColl(&op2, &op1, pB, &hp3);
         if (plane3 == 8) {
             return 0;
+        }
+        GetBoundsEdge(&pPoint_list[n], &edge, pB, plane1, plane3, &op2, &hp1, &hp2, c->collision_flag);
+        GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane2, plane3, &op2, &hp1, &hp2, c->collision_flag);
+        GetPlaneNormal(&pNorm_list[n], plane3);
+        BrVector3Copy(&pNorm_list[n + 1], &pNorm_list[n]);
+        return 2;
+    } else if (plane1 == 8 && plane2 != 8) {
+        BrMatrix34ApplyP(&a, p1, pMold);
+        plane3 = LineBoxColl(&a, p1, pB, &hp3);
+        if (plane3 == 8) {
+            return 0;
+        }
+        BrVector3Copy(&pPoint_list[n], &hp3);
+        GetPlaneNormal(&pNorm_list[n], plane2);
+        if (plane2 == plane3 || (plane3 ^ plane2) == 4) {
+            return 1;
+        }
+        GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane2, plane3, p1, &hp2, &hp3, c->collision_flag);
+        BrVector3Sub(&op1, p1, p2);
+        BrVector3Cross(&pNorm_list[n + 1], &edge, &op1);
+        BrVector3Normalise(&pNorm_list[n + 1], &pNorm_list[n + 1]);
+        d = (plane2 - 1) & 3;
+        if ((pNorm_list[n + 1].v[d] < 0.f) == (plane2 & 4) >> 2) {
+            BrVector3Negate(&pNorm_list[n + 1], &pNorm_list[n + 1]);
+        }
+        BrVector3Copy(&op1, &pNorm_list[n + 1]);
+        BrMatrix34ApplyV(&pNorm_list[n + 1], &op1, pMold);
+        return 2;
+    } else if (plane2 == 8 && plane1 != 8) {
+        BrMatrix34ApplyP(&b, p2, pMold);
+        plane3 = LineBoxColl(&b, p2, pB, &hp3);
+        if (plane3 == 8) {
+            return 0;
+        }
+        pPoint_list[n] = hp3;
+        GetPlaneNormal(&pNorm_list[n], plane1);
+        if (plane1 == plane3 || (plane3 ^ plane1) == 4) {
+            return 1;
+        }
+        GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane1, plane3, p2, &hp1, &hp3, c->collision_flag);
+        BrVector3Sub(&op1, p1, p2);
+        BrVector3Cross(&pNorm_list[n + 1], &edge, &op1);
+        BrVector3Normalise(&pNorm_list[n + 1], &pNorm_list[n + 1]);
+        d = (plane1 - 1) & 3;
+        if ((pNorm_list[n + 1].v[d] < 0.f) == (plane1 & 4) >> 2) {
+            BrVector3Negate(&pNorm_list[n + 1], &pNorm_list[n + 1]);
+        }
+        BrVector3Copy(&op1, &pNorm_list[n + 1]);
+        BrMatrix34ApplyV(&pNorm_list[n + 1], &op1, pMold);
+        return 2;
+    } else if (plane1 != 8 && plane2 != 8) {
+        BrVector3Add(&op1, &hp2, &hp1);
+        BrVector3Scale(&op1, &op1, .5f);
+        BrMatrix34ApplyP(&op2, &op1, pMold);
+        plane3 = LineBoxColl(&op2, &op1, pB, &hp3);
+        if (plane3 == 8 || plane3 == 0) {
+            return 0;
+        }
+        if (plane1 == plane3 || plane2 == plane3) {
+            GetBoundsEdge(&pPoint_list[n], &edge, pB, plane1, plane2, &op2, &hp1, &hp2, c->collision_flag);
+            BrVector3Sub(&op1, &hp1, &hp2);
+            BrVector3Cross(&op2, &edge, &op1);
+            BrVector3Normalise(&pNorm_list[n], &op2);
+            BrVector3Add(&op1, &pB->max, &pB->min);
+            BrVector3Scale(&op1, &op1, .5f);
+            BrVector3Sub(&op1, &pPoint_list[n], &op1);
+            if (BrVector3Dot(&pNorm_list[n], &op1) > 0.f) {
+                BrVector3Negate(&pNorm_list[n], &pNorm_list[n]);
+            }
+            BrVector3Copy(&op1, &pNorm_list[n]);
+            BrMatrix34ApplyV(&pNorm_list[n], &op1, pMold);
+            return 1;
         } else {
-            GetBoundsEdge(&pPoint_list[n], &edge, pB, plane1, plane3, &op2, &hp1, &hp2, c->collision_flag);
-            GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane2, plane3, &op2, &hp1, &hp2, c->collision_flag);
+            GetBoundsEdge(&pPoint_list[n], &edge, pB, plane1, plane3, &hp3, &hp1, &hp2, c->collision_flag);
+            GetBoundsEdge(&pPoint_list[n + 1], &edge, pB, plane2, plane3, &hp3, &hp1, &hp2, c->collision_flag);
             GetPlaneNormal(&pNorm_list[n], plane3);
-            pNorm_list[n + 1] = pNorm_list[n];
+            BrVector3Copy(&pNorm_list[n + 1], &pNorm_list[n]);
             return 2;
         }
+    } else if (plane1 == 8 && plane2 == 8) {
+        BrMatrix34ApplyP(&op1, p1, pMold);
+        plane3 = LineBoxColl(&op1, p1, pB, &pPoint_list[n]);
+        GetPlaneNormal(&pNorm_list[n], plane3);
+        d = n + (plane3 != 8);
+        BrMatrix34ApplyP(&op1, p2, pMold);
+        plane3 = LineBoxColl(&op1, p2, pB, &pPoint_list[d]);
+        GetPlaneNormal(&pNorm_list[d], plane3);
+        return (n != d) + (plane3 != 8);
+    } else {
+        return 0;
     }
 }
 
@@ -3990,9 +3938,7 @@ void GetPlaneNormal(br_vector3* n, int p) {
     LOG_TRACE("(%p, %d)", n, p);
 
     d = (p - 1) & 3;
-    n->v[0] = 0.0;
-    n->v[1] = 0.0;
-    n->v[2] = 0.0;
+    BrVector3Set(n, 0.f, 0.f, 0.f);
     if ((p & 4) != 0) {
         n->v[d] = 1.0;
     } else {
@@ -4012,15 +3958,9 @@ int GetBoundsEdge(br_vector3* pos, br_vector3* edge, br_bounds* pB, int plane1,
 
     d1 = (plane1 - 1) & 3;
     d2 = (plane2 - 1) & 3;
-    n.v[0] = b->v[0] - a->v[0];
-    n.v[1] = b->v[1] - a->v[1];
-    n.v[2] = b->v[2] - a->v[2];
-    p.v[0] = c->v[0] - a->v[0];
-    p.v[1] = c->v[1] - a->v[1];
-    p.v[2] = c->v[2] - a->v[2];
-    q.v[0] = p.v[2] * n.v[1] - p.v[1] * n.v[2];
-    q.v[1] = n.v[2] * p.v[0] - p.v[2] * n.v[0];
-    q.v[2] = p.v[1] * n.v[0] - n.v[1] * p.v[0];
+    BrVector3Sub(&n, b, a);
+    BrVector3Sub(&p, c, a);
+    BrVector3Cross(&q, &n, &p);
     if ((plane1 & 4) != 0) {
         pos->v[d1] = pB->min.v[d1];
     } else {
@@ -4032,11 +3972,11 @@ int GetBoundsEdge(br_vector3* pos, br_vector3* edge, br_bounds* pB, int plane1,
         pos->v[d2] = pB->max.v[d2];
     }
     d3 = 3 - d1 - d2;
-    edge->v[d1] = 0.0;
-    edge->v[d2] = 0.0;
-    edge->v[d3] = 1.0;
+    edge->v[d1] = 0.f;
+    edge->v[d2] = 0.f;
+    edge->v[d3] = 1.f;
     if ((flag & 1) != 0) {
-        pos->v[d3] = (c->v[d3] + b->v[d3]) / 2.0;
+        pos->v[d3] = (c->v[d3] + b->v[d3]) / 2.f;
     } else {
         pos->v[d3] = a->v[d3] - ((pos->v[d2] - a->v[d2]) * q.v[d2] + (pos->v[d1] - a->v[d1]) * q.v[d1]) / q.v[d3];
     }
diff --git a/src/DETHRACE/common/cutscene.c b/src/DETHRACE/common/cutscene.c
index e98e33e9..2d41a9dc 100644
--- a/src/DETHRACE/common/cutscene.c
+++ b/src/DETHRACE/common/cutscene.c
@@ -234,7 +234,11 @@ void DoFullVersionPowerpoint() {
 
     FadePaletteDown();
     DRSetPalette(gRender_palette);
-    ShowCutScene(9, 0, 8503, gCut_delay_4);
+    if (harness_game_info.mode == eGame_splatpack_demo) {
+        PlaySmackerFile("DEMOEND.SMK");
+    } else {
+        ShowCutScene(9, 0, 8503, gCut_delay_4);
+    }
     FadePaletteDown();
 
     gLast_demo_end_anim = PDGetTotalTime();
diff --git a/src/DETHRACE/common/init.c b/src/DETHRACE/common/init.c
index 9043b6ef..4f4b54bc 100644
--- a/src/DETHRACE/common/init.c
+++ b/src/DETHRACE/common/init.c
@@ -424,7 +424,7 @@ void InitGame(int pStart_race) {
     gNo_races_yet = 1;
     NetPlayerStatusChanged(ePlayer_status_loading);
     gProgram_state.current_race_index = pStart_race;
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         gProgram_state.current_car.power_up_levels[0] = gDemo_armour;
         gProgram_state.current_car.power_up_levels[1] = gDemo_power;
         gProgram_state.current_car.power_up_levels[2] = gDemo_offensive;
diff --git a/src/DETHRACE/common/loading.c b/src/DETHRACE/common/loading.c
index 14a6864f..9391f05f 100644
--- a/src/DETHRACE/common/loading.c
+++ b/src/DETHRACE/common/loading.c
@@ -1687,7 +1687,7 @@ void MungeWindscreen(br_model* pModel) {
 void SetModelFlags(br_model* pModel, int pOwner) {
     LOG_TRACE("(%p, %d)", pModel, pOwner);
 
-    if (pModel && pModel->nfaces) {
+    if (pModel != NULL&& pModel->nfaces != 0) {
 #if defined(DETHRACE_FIX_BUGS) /* Show Squad Car in the wreck gallery. */
         if (gAusterity_mode) {
 #else
@@ -1795,7 +1795,12 @@ void LoadCar(char* pCar_name, tDriver pDriver, tCar_spec* pCar_spec, int pOwner,
         FatalError(kFatalError_FileCorrupt_S, pCar_name);
     }
     if (*pDriver_name != '\0') {
+#if defined(DETHRACE_FIX_BUGS)
+        // Make sure to not read and write out of bounds.
+        memcpy(pCar_spec->driver_name, pDriver_name, MIN(sizeof(pCar_spec->driver_name), strlen(pDriver_name)));
+#else
         memcpy(pCar_spec->driver_name, pDriver_name, sizeof(pCar_spec->driver_name));
+#endif
         pCar_spec->driver_name[sizeof(pCar_spec->driver_name) - 1] = '\0';
     } else {
         strcpy(pCar_spec->driver_name, "X");
@@ -2430,11 +2435,11 @@ void LoadRaces(tRace_list_spec* pRace_list, int* pCount, int pRace_type_index) {
     *pCount = number_of_racers;
     fclose(f);
     j = 0;
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         j = 99;
     }
     for (i = 0; i < number_of_racers; i++) {
-        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
             pRace_list[i].suggested_rank = gDemo_rank;
             pRace_list[i].rank_required = j;
             j -= 3;
diff --git a/src/DETHRACE/common/loadsave.c b/src/DETHRACE/common/loadsave.c
index c318b202..6fabd590 100644
--- a/src/DETHRACE/common/loadsave.c
+++ b/src/DETHRACE/common/loadsave.c
@@ -446,7 +446,7 @@ int DoLoadGame() {
     int result;
     LOG_TRACE("()");
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         DoFeatureUnavailableInDemo();
         return 0;
     }
@@ -933,7 +933,7 @@ int SaveGameInterface(int pDefault_choice) {
 void DoSaveGame(int pSave_allowed) {
     LOG_TRACE("()");
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         DoFeatureUnavailableInDemo();
         return;
     }
diff --git a/src/DETHRACE/common/main.c b/src/DETHRACE/common/main.c
index 9193be78..55440ffb 100644
--- a/src/DETHRACE/common/main.c
+++ b/src/DETHRACE/common/main.c
@@ -23,7 +23,7 @@
 void QuitGame() {
     LOG_TRACE("()");
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         DoDemoGoodbye();
     }
 
diff --git a/src/DETHRACE/common/mainloop.c b/src/DETHRACE/common/mainloop.c
index e74c225d..1fddbc49 100644
--- a/src/DETHRACE/common/mainloop.c
+++ b/src/DETHRACE/common/mainloop.c
@@ -438,7 +438,7 @@ void CheckTimer() {
             RaceCompleted(eRace_over_out_of_time);
         }
 
-        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
             if (harness_game_config.demo_timeout != 0) {
                 time_left = harness_game_config.demo_timeout - GetRaceTime();
                 time_in_seconds = (time_left + 500) / 1000;
diff --git a/src/DETHRACE/common/mainmenu.c b/src/DETHRACE/common/mainmenu.c
index 5715d06d..672f2a1c 100644
--- a/src/DETHRACE/common/mainmenu.c
+++ b/src/DETHRACE/common/mainmenu.c
@@ -31,7 +31,7 @@ char* gPixels_copy__mainmenu; // suffix added to avoid duplicate symbol
 int MainMenuDone1(int pCurrent_choice, int pCurrent_mode, int pGo_ahead, int pEscaped, int pTimed_out) {
     LOG_TRACE("(%d, %d, %d, %d, %d)", pCurrent_choice, pCurrent_mode, pGo_ahead, pEscaped, pTimed_out);
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         if (pCurrent_mode == 0) {
             if (pCurrent_choice == 7) {
                 PreloadBunchOfFlics(7);
@@ -74,7 +74,7 @@ int MainMenuDone1(int pCurrent_choice, int pCurrent_mode, int pGo_ahead, int pEs
 int MainMenuDone2(int pCurrent_choice, int pCurrent_mode, int pGo_ahead, int pEscaped, int pTimed_out) {
     LOG_TRACE("(%d, %d, %d, %d, %d)", pCurrent_choice, pCurrent_mode, pGo_ahead, pEscaped, pTimed_out);
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         if (pCurrent_mode == 0) {
             if (pCurrent_choice == 4) {
                 PreloadBunchOfFlics(7);
diff --git a/src/DETHRACE/common/newgame.c b/src/DETHRACE/common/newgame.c
index 2e487cb1..e648380a 100644
--- a/src/DETHRACE/common/newgame.c
+++ b/src/DETHRACE/common/newgame.c
@@ -331,7 +331,7 @@ int DoOnePlayerStart() {
                 memcpy(&gProgram_state, &saved_state, sizeof(tProgram_state));
                 return 0;
             }
-            if ((harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) && gProgram_state.frank_or_anniness != eFrankie) {
+            if ((harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) && gProgram_state.frank_or_anniness != eFrankie) {
                 DoFeatureUnavailableInDemo();
                 memset(&gProgram_state, 0, sizeof(gProgram_state));
                 return 0;
@@ -851,7 +851,7 @@ int DoMultiPlayerStart() {
     int car_index;
     LOG_TRACE("()");
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         SuspendPendingFlic();
         DoFeatureUnavailableInDemo();
         return 0;
diff --git a/src/DETHRACE/common/racestrt.c b/src/DETHRACE/common/racestrt.c
index 9c4aa3e7..778064e7 100644
--- a/src/DETHRACE/common/racestrt.c
+++ b/src/DETHRACE/common/racestrt.c
@@ -1672,7 +1672,7 @@ tSO_result DoSelectRace(int* pSecond_time_around) {
             DisposeFlicPanel(0);
 
             if (result == 2) {
-                if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+                if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
                     DoFeatureUnavailableInDemo();
                 } else {
                     RunFlic(192);
diff --git a/src/DETHRACE/common/racesumm.c b/src/DETHRACE/common/racesumm.c
index 38268155..0fddf5f1 100644
--- a/src/DETHRACE/common/racesumm.c
+++ b/src/DETHRACE/common/racesumm.c
@@ -1214,7 +1214,7 @@ tSO_result DoEndRaceSummary(int* pFirst_summary_done, tRace_result pRace_result)
     tSO_result result;
     LOG_TRACE("(%p, %d)", pFirst_summary_done, pRace_result);
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         gRank_etc_munged = 1;
         DoEndRaceSummary2();
         return eSO_continue;
diff --git a/src/DETHRACE/common/spark.c b/src/DETHRACE/common/spark.c
index d1737b6b..84e15150 100644
--- a/src/DETHRACE/common/spark.c
+++ b/src/DETHRACE/common/spark.c
@@ -24,7 +24,7 @@ int gShrapnel_flags;
 br_model* gShrapnel_model[2];
 int gSmoke_flags;
 int gSmoke_num;
-int gOffset;
+int gOffset = 0;
 int gColumn_flags;
 int gNext_column;
 br_pixelmap* gBlack_smoke_shade_table;
@@ -838,7 +838,7 @@ void SmokeLine(int l, int x, br_scalar zbuff, int r_squared, tU8* scr_ptr, tU16*
     if (gProgram_state.cockpit_on) {
         depth_ptr += gOffset;
     }
-    z = (1.0 - zbuff) * 32768.0f;
+    z = (1.f - zbuff) * 32768.0f;
     r_multiplier_int = r_multiplier * 65536.0f;
     shade_offset_int = shade_offset * 65536.0f;
 
@@ -897,7 +897,7 @@ void SmokeCircle(br_vector3* o, br_scalar r, br_scalar extra_z, br_scalar streng
         return;
     }
     shade_ptr = (tU8*)pShade_table->pixels + pShade_table->row_bytes * (pShade_table->base_y + 1);
-    shade_offset = strength * 14.99;
+    shade_offset = strength * 14.99f;
     r_multiplier = shade_offset / (double)max_r_squared;
     z_multiplier = extra_z / (double)max_r_squared;
     max_x = pRender_screen->width - ox - 1;
@@ -910,7 +910,7 @@ void SmokeCircle(br_vector3* o, br_scalar r, br_scalar extra_z, br_scalar streng
     osp = scr_ptr;
     odp = depth_ptr;
     if (pRender_screen->height > oy && oy + ry >= 0.0) {
-        r_squared = (r * r);
+        r_squared = r * r;
         inc = -r;
         y = 0;
         y_limit = ry;
@@ -951,7 +951,7 @@ void SmokeCircle(br_vector3* o, br_scalar r, br_scalar extra_z, br_scalar streng
             if (y_limit <= y) {
                 break;
             }
-            ++y;
+            y++;
             scr_ptr -= pRender_screen->row_bytes;
             depth_ptr -= pDepth_buffer->row_bytes / 2;
             for (r_squared += (2 * y - 1) * aspect_squared; max_r_squared < r_squared && inc < 0; r_squared += 2 * inc - 1) {
@@ -961,19 +961,19 @@ void SmokeCircle(br_vector3* o, br_scalar r, br_scalar extra_z, br_scalar streng
                 l -= 2;
             }
             gOffset += IRandomBetween(-1, 1);
-            if (gOffset > r / 5.0) {
-                gOffset = r / 5.0;
+            if (gOffset > r / 5.f) {
+                gOffset = r / 5.f;
             }
-            if (gOffset < -(r / 5.0)) {
-                gOffset = -(r / 5.0);
+            if (gOffset < -(r / 5.f)) {
+                gOffset = -(r / 5.f);
             }
         }
     }
     if (pAspect < 1.0) {
-        aspect_squared = 9.0;
-        ry = r / 3.0;
+        aspect_squared = 9.f;
+        ry = r / 3.f;
     }
-    if (oy > 0 && oy <= pRender_screen->height + ry - 2.0) {
+    if (oy > 0 && oy <= pRender_screen->height + ry - 2.f) {
         r_squared = (r * r);
         inc = -r;
         y = 0;
@@ -989,7 +989,7 @@ void SmokeCircle(br_vector3* o, br_scalar r, br_scalar extra_z, br_scalar streng
             inc = -sqrtf(max_r_squared - r_squared);
             r_squared += inc * inc;
         }
-        if (oy - ry < 0.0) {
+        if (oy - ry < 0.f) {
             y_limit = oy;
         }
         l = -2 * inc;
diff --git a/src/DETHRACE/common/structur.c b/src/DETHRACE/common/structur.c
index 2189dd60..823413ce 100644
--- a/src/DETHRACE/common/structur.c
+++ b/src/DETHRACE/common/structur.c
@@ -359,7 +359,7 @@ void SelectOpponents(tRace_info* pRace_info) {
     int had_scum;
     LOG_TRACE("(%p)", pRace_info);
 
-    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+    if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
         pRace_info->number_of_racers = OPPONENT_COUNT;
         for (i = 0; i < OPPONENT_COUNT; i++) {
             pRace_info->opponent_list[i].index = gDemo_opponents[i];
@@ -573,7 +573,7 @@ void DoGame() {
                             DisposeOpponentsCars(&gCurrent_race);
                         }
                         DisposeTrack();
-                        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo) {
+                        if (harness_game_info.mode == eGame_carmageddon_demo || harness_game_info.mode == eGame_splatpack_demo || harness_game_info.mode == eGame_splatpack_xmas_demo) {
                             DoFullVersionPowerpoint();
                         }
                         gProgram_state.loaded = 0;
diff --git a/src/DETHRACE/common/utility.c b/src/DETHRACE/common/utility.c
index e94b8086..20fd51bd 100644
--- a/src/DETHRACE/common/utility.c
+++ b/src/DETHRACE/common/utility.c
@@ -26,16 +26,16 @@
 #define MIN_SERVICE_INTERVAL 200
 // <<
 
-int gIn_check_quit;
-tU32 gLost_time;
+int gIn_check_quit = 0;
+tU32 gLost_time = 0;
 #if BR_ENDIAN_BIG
-tU32 gLong_key[4] = { 0x6C1B995F, 0xB9CD5F13, 0xCB04200E, 0x5E1CA10E };
-tU32 gOther_long_key[4] = { 0x67A8D626, 0xB6DD451B, 0x327E2213, 0x15C29437};
+tU32 gLong_key[4] = { 0x6c1b995f, 0xb9cd5f13, 0xcb04200e, 0x5e1ca10e };
+tU32 gOther_long_key[4] = { 0x67a8d626, 0xb6dd451b, 0x327e2213, 0x15c29437};
 #else
-tU32 gLong_key[4] = { 0x5F991B6C, 0x135FCDB9, 0x0E2004CB, 0x0EA11C5E };
-tU32 gOther_long_key[4] = { 0x26D6A867, 0x1B45DDB6, 0x13227E32, 0x3794C215 };
+tU32 gLong_key[4] = { 0x5f991b6c, 0x135fcdb9, 0x0e2004cb, 0x0ea11c5e };
+tU32 gOther_long_key[4] = { 0x26d6a867, 0x1b45ddb6, 0x13227e32, 0x3794c215 };
 #endif
-int gEncryption_method;
+int gEncryption_method = 0;
 char* gMisc_strings[250];
 br_pixelmap* g16bit_palette;
 br_pixelmap* gSource_for_16bit_palette;
@@ -120,13 +120,11 @@ void EncodeLine(char* pS) {
 
     len = strlen(pS);
     key = (char*)gLong_key;
-    if (!gEncryption_method) {
-        strcpy(the_path, gApplication_path);
-        strcat(the_path, gDir_separator);
-        strcat(the_path, "GENERAL.TXT");
+    if (gEncryption_method == 0) {
+        PathCat(the_path, gApplication_path, "GENERAL.TXT");
 
         test = fopen(the_path, "rt");
-        if (test) {
+        if (test != NULL) {
             fgets(s, 256, test);
             if (s[0] != '@') {
                 gEncryption_method = 2;
@@ -144,45 +142,53 @@ void EncodeLine(char* pS) {
         }
     }
     while (len > 0 && (pS[len - 1] == '\r' || pS[len - 1] == '\n')) {
-        --len;
-        pS[len] = 0;
+        len--;
+        pS[len] = '\0';
     }
 
     seed = len % 16;
+
     for (i = 0; i < len; i++) {
         c = pS[i];
+#if defined(DETHRACE_FIX_BUGS)
+        // When loading game data, Carmageddon does not switch the XOR cypher when the comments start.
         if (i >= 2) {
             if (pS[i - 1] == '/' && pS[i - 2] == '/') {
                 key = (char*)gOther_long_key;
             }
         }
+#endif
         if (gEncryption_method == 1) {
             if (c == '\t') {
-                c = 0x80;
+                c = 0x9f;
             }
+
             c -= 0x20;
-            if (!(c & 0x80)) {
-                c = (c ^ key[seed]) & 0x7f;
-                c += 0x20;
-            }
+            c ^= key[seed];
+            c &= 0x7f;
+            c += 0x20;
+
             seed += 7;
-            seed = seed % 16;
+            seed %= 16;
 
-            if (c == 0x80) {
+            if (c == 0x9f) {
                 c = '\t';
             }
         } else {
             if (c == '\t') {
-                c = 0x9f;
+                c = 0x80;
             }
+
             c -= 0x20;
-            c = (c ^ key[seed]) & 0x7f;
+            if ((c & 0x80) == 0) {
+                c ^= key[seed] & 0x7f;
+            }
             c += 0x20;
 
             seed += 7;
-            seed = seed % 16;
+            seed %= 16;
 
-            if (c == 0x9f) {
+            if (c == 0x80) {
                 c = '\t';
             }
         }
@@ -343,7 +349,7 @@ float tandeg(float pAngle) {
     LOG_TRACE("(%f)", pAngle);
 
     pAngle = DEG_TO_RAD(pAngle);
-    return sin(pAngle) / cos(pAngle);
+    return sinf(pAngle) / cosf(pAngle);
 }
 
 // IDA: tU32 __usercall GetFileLength@<EAX>(FILE *pF@<EAX>)
@@ -368,7 +374,7 @@ br_pixelmap* DRPixelmapAllocate(br_uint_8 pType, br_uint_16 pW, br_uint_16 pH, v
     br_pixelmap* the_map;
 
     the_map = BrPixelmapAllocate(pType, pW, pH, pPixels, pFlags);
-    if (the_map) {
+    if (the_map != NULL) {
         the_map->origin_y = 0;
         the_map->origin_x = 0;
     }
@@ -581,14 +587,12 @@ br_uint_32 DRActorEnumRecurseWithTrans(br_actor* pActor, br_matrix34* pMatrix, b
 int sign(int pNumber) {
     LOG_TRACE("(%d)", pNumber);
 
-    if (pNumber < 1) {
-        if (pNumber < 0) {
-            return -1;
-        } else {
-            return 0;
-        }
-    } else {
+    if (pNumber > 0) {
         return 1;
+    } else if (pNumber < 0) {
+        return -1;
+    } else {
+        return 0;
     }
 }
 
@@ -1157,8 +1161,8 @@ void DecodeLine2(char* pS) {
     len = strlen(pS);
     key = (char*)gLong_key;
     while (len > 0 && (pS[len - 1] == '\r' || pS[len - 1] == '\n')) {
-        --len;
-        pS[len] = 0;
+        len--;
+        pS[len] = '\0';
     }
     seed = len % 16;
     for (i = 0; i < len; i++) {
@@ -1170,31 +1174,34 @@ void DecodeLine2(char* pS) {
         }
         if (gEncryption_method == 1) {
             if (c == '\t') {
-                c = 0x80;
+                c = 0x9f;
             }
+
             c -= 0x20;
-            if (!(c & 0x80)) {
-                c = (c ^ key[seed]) & 0x7f;
-                c += 0x20;
-            }
+            c ^= key[seed];
+            c &= 0x7f;
+            c += 0x20;
+
             seed += 7;
-            seed = seed % 16;
+            seed %= 16;
 
-            if (c == 0x80) {
+            if (c == 0x9f) {
                 c = '\t';
             }
         } else {
             if (c == '\t') {
-                c = 0x9f;
+                c = 0x80;
             }
             c -= 0x20;
-            c = (c ^ key[seed]) & 0x7f;
+            if ((c & 0x80) == 0) {
+                c ^= key[seed] & 0x7f;
+            }
             c += 0x20;
 
             seed += 7;
-            seed = seed % 16;
+            seed %= 16;
 
-            if (c == 0x9f) {
+            if (c == 0x80) {
                 c = '\t';
             }
         }
@@ -1214,37 +1221,39 @@ void EncodeLine2(char* pS) {
     len = strlen(pS);
     count = 0;
     key = (char*)gLong_key;
-    while (len > 0 && (pS[len - 1] == 13 || pS[len - 1] == 10)) {
-        --len;
-        pS[len] = 0;
+    while (len > 0 && (pS[len - 1] == '\r' || pS[len - 1] == '\n')) {
+        len--;
+        pS[len] = '\0';
     }
 
     seed = len % 16;
 
-    for (i = 0; i < len; ++pS) {
-        if (count == 2)
+    for (i = 0; i < len; i++) {
+        if (count == 2) {
             key = (char*)gOther_long_key;
-        if (*pS == '/') {
-            ++count;
+        }
+        if (pS[i] == '/') {
+            count++;
         } else {
             count = 0;
         }
-        if (*pS == '\t') {
-            *pS = 0x80;
+        if (pS[i] == '\t') {
+            pS[i] = 0x80;
         }
-        c = *pS - 0x20;
-        if (!(c & 0x80)) {
-            c = c ^ (key[seed] & 0x7F);
-            c += 0x20;
+
+        c = pS[i] - 0x20;
+        if ((c & 0x80) == 0) {
+            c ^= key[seed] & 0x7f;
         }
+        c += 0x20;
+
         seed += 7;
-        seed = seed % 16;
+        seed %= 16;
 
         if (c == 0x80) {
             c = '\t';
         }
-        *pS = c;
-        ++i;
+        pS[i] = c;
     }
 }
 
@@ -1264,11 +1273,11 @@ void EncodeFile(char* pThe_path) {
 
     len = strlen(pThe_path);
     strcpy(new_file, pThe_path);
-    strcat(new_file, "ENC");
+    strcpy(&new_file[len - 3], "ENC");
 
     f = fopen(pThe_path, "rt");
     if (f == NULL) {
-        FatalError(kFatalError_Open_S, new_file);
+        FatalError(kFatalError_Open_S, pThe_path);
     }
 
     ch = fgetc(f);
@@ -1287,37 +1296,44 @@ void EncodeFile(char* pThe_path) {
     result = &line[1];
 
     while (!feof(f)) {
-        fgets(result, 256, f);
+        s = fgets(result, 256, f);
+
+        if (s == NULL) {
+            continue;
+        }
 
-        if (ch == '@') {
+        if (result[0] == '@') {
             decode = 1;
         } else {
             decode = 0;
-            s = &result[1];
-            while (line[0] == ' ' || line[0] == '\t') {
-                memmove(result, s, strlen(result));
+            // Strip leading whitespace
+            while (result[0] == ' ' || result[0] == '\t') {
+                memmove(result, &result[1], strlen(result));
             }
         }
 
-        if (decode == 0) {
-            EncodeLine2(result + decode);
+        if (decode) {
+            DecodeLine2(&result[decode]);
         } else {
-            DecodeLine2(result + decode);
+            EncodeLine2(&result[decode]);
         }
 
         line[0] = '@';
         fputs(&line[decode * 2], d);
         count = -1;
-        ch = fgetc(f);
-        while (ch == '\r' || ch == '\n') {
+        while (1) {
             count++;
+            ch = fgetc(f);
+            if (ch != '\r' && ch != '\n') {
+                break;
+            }
         }
-        if (count >= 2) {
-            fputc(0x0d, d);
-            fputc(0x0a, d);
+        if (count > 2) {
+            fputc('\r', d);
+            fputc('\n', d);
         }
-        fputc(0x0d, d);
-        fputc(0x0a, d);
+        fputc('\r', d);
+        fputc('\n', d);
 
         if (ch != -1) {
             ungetc(ch, f);
diff --git a/src/DETHRACE/common/world.c b/src/DETHRACE/common/world.c
index bf9ebcd8..96330835 100644
--- a/src/DETHRACE/common/world.c
+++ b/src/DETHRACE/common/world.c
@@ -4098,7 +4098,15 @@ void StopGroovidelic(br_actor* pActor) {
     tGroovidelic_spec* the_groove;
     LOG_TRACE("(%p)", pActor);
 
-    STUB();
+    for (i = 0; i < gGroovidelics_array_size; i++) {
+        the_groove = &gGroovidelics_array[i];
+        if (the_groove->actor == pActor) {
+            if (the_groove->path_interrupt_status == eInterrupt_none && the_groove->object_interrupt_status == eInterrupt_none) {
+                GrooveThisDelic(the_groove, gPrevious_groove_times[1], 1);
+            }
+            return;
+        }
+    }
 }
 
 // IDA: void __usercall SetGrooveInterrupt(int pGroove_index@<EAX>, br_matrix34 *pMatrix@<EDX>, int pPath_interrupt@<EBX>, int pObject_interrupt@<ECX>, float pPath_resumption, float pObject_resumption)
diff --git a/src/harness/CMakeLists.txt b/src/harness/CMakeLists.txt
index 24d4db8e..eb3229bb 100644
--- a/src/harness/CMakeLists.txt
+++ b/src/harness/CMakeLists.txt
@@ -16,6 +16,10 @@ target_include_directories(harness
         include
 )
 
+if(DETHRACE_FIX_BUGS)
+    target_compile_definitions(harness PRIVATE DETHRACE_FIX_BUGS)
+endif()
+
 target_link_libraries(harness PRIVATE brender compile_with_werror)
 
 if(WIN32)
@@ -82,6 +86,8 @@ if (IO_PLATFORM STREQUAL "SDL_OpenGL")
         resources/3d_vert.glsl.h
         resources/3d_frag.glsl.h
     )
+    target_include_directories(harness PRIVATE "${dethrace_SOURCE_DIR}/src/DETHRACE/common")
+    target_include_directories(harness PRIVATE "${dethrace_SOURCE_DIR}/src/S3/include")
     target_link_libraries(harness PRIVATE SDL2::SDL2 glad)
 endif()
 
diff --git a/src/harness/harness.c b/src/harness/harness.c
index 27683cd5..11bbc9bd 100644
--- a/src/harness/harness.c
+++ b/src/harness/harness.c
@@ -93,13 +93,13 @@ void Harness_DetectGameMode() {
             printf("Game mode: Splat Pack\n");
         } else if (access("DATA/RACES/TINSEL.TXT", F_OK) != -1) {
             // Only the the splat x-mas demo has the tinsel track
-            harness_game_info.defines.INTRO_SMK_FILE = "";
+            harness_game_info.defines.INTRO_SMK_FILE = "MIX_INTR.SMK";
             harness_game_info.defines.GERMAN_LOADSCRN = "";
-            harness_game_info.mode = eGame_splatpack_demo;
+            harness_game_info.mode = eGame_splatpack_xmas_demo;
             printf("Game mode: Splat Pack X-mas demo\n");
         } else {
             // Assume we're using the splatpack demo
-            harness_game_info.defines.INTRO_SMK_FILE = "";
+            harness_game_info.defines.INTRO_SMK_FILE = "MIX_INTR.SMK";
             harness_game_info.defines.GERMAN_LOADSCRN = "";
             harness_game_info.mode = eGame_splatpack_demo;
             printf("Game mode: Splat Pack demo\n");
@@ -165,6 +165,7 @@ void Harness_DetectGameMode() {
         harness_game_info.defines.ascii_shift_table = demo_ascii_shift_table;
         break;
     case eGame_splatpack_demo:
+    case eGame_splatpack_xmas_demo:
         harness_game_info.defines.ascii_table = splatpack_xmasdemo_ascii_table;
         harness_game_info.defines.ascii_shift_table = splatpack_xmasdemo_ascii_shift_table;
         break;
@@ -192,6 +193,8 @@ void Harness_Init(int* argc, char* argv[]) {
     harness_game_config.enable_diagnostics = 0;
     // no volume multiplier
     harness_game_config.volume_multiplier = 1.0f;
+    // start window in windowed mode
+    harness_game_config.start_full_screen = 0;
 
     // install signal handler by default
     harness_game_config.install_signalhandler = 1;
@@ -278,6 +281,9 @@ int Harness_ProcessCommandLine(int* argc, char* argv[]) {
             harness_game_config.volume_multiplier = atof(s + 1);
             LOG_INFO("Volume multiplier set to %f", harness_game_config.volume_multiplier);
             handled = 1;
+        } else if (strcasecmp(argv[i], "--full-screen") == 0) {
+            harness_game_config.start_full_screen = 1;
+            handled = 1;
         }
 
         if (handled) {
diff --git a/src/harness/include/harness/config.h b/src/harness/include/harness/config.h
index a4179e52..1240e3aa 100644
--- a/src/harness/include/harness/config.h
+++ b/src/harness/include/harness/config.h
@@ -7,6 +7,7 @@ typedef enum tHarness_game_type {
     eGame_splatpack,
     eGame_carmageddon_demo,
     eGame_splatpack_demo,
+    eGame_splatpack_xmas_demo,
 } tHarness_game_type;
 
 typedef enum {
@@ -37,6 +38,7 @@ typedef struct tHarness_game_config {
     unsigned demo_timeout;
     int enable_diagnostics;
     float volume_multiplier;
+    int start_full_screen;
 
     int install_signalhandler;
 } tHarness_game_config;
diff --git a/src/harness/io_platforms/sdl_gl.c b/src/harness/io_platforms/sdl_gl.c
index 39410ae1..eebefdc3 100644
--- a/src/harness/io_platforms/sdl_gl.c
+++ b/src/harness/io_platforms/sdl_gl.c
@@ -6,8 +6,14 @@
 
 #include "../renderers/gl/gl_renderer.h"
 #include "../renderers/renderer.h"
+
+#include "harness/config.h"
 #include "harness/trace.h"
 
+#include "globvars.h"
+#include "grafdata.h"
+#include "pd/sys.h"
+
 #define ARRAY_LEN(array) (sizeof((array)) / sizeof((array)[0]))
 
 int scancode_map[123];
@@ -129,7 +135,6 @@ struct {
     float x;
     float y;
 } sdl_window_scale;
-int is_full_screen = 0;
 
 tRenderer gl_renderer = {
     GLRenderer_Init,
@@ -175,6 +180,10 @@ tRenderer* Window_Create(char* title, int width, int height, int pRender_width,
     sdl_window_scale.x = ((float)pRender_width) / width;
     sdl_window_scale.y = ((float)pRender_height) / height;
 
+    if (harness_game_config.start_full_screen) {
+        SDL_SetWindowFullscreen(window, SDL_WINDOW_FULLSCREEN_DESKTOP);
+    }
+
     SDL_ShowCursor(SDL_DISABLE);
 
     context = SDL_GL_CreateContext(window);
@@ -218,8 +227,7 @@ void Window_PollEvents() {
                     }
                 } else if (event.key.type == SDL_KEYUP) {
                     if (is_only_key_modifier(event.key.keysym.mod, KMOD_ALT)) {
-                        is_full_screen = !is_full_screen;
-                        SDL_SetWindowFullscreen(window, is_full_screen ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0);
+                        SDL_SetWindowFullscreen(window, (SDL_GetWindowFlags(window) & SDL_WINDOW_FULLSCREEN_DESKTOP) ? 0 : SDL_WINDOW_FULLSCREEN_DESKTOP);
                     }
                 }
             }
@@ -304,6 +312,15 @@ void Input_GetMousePosition(int* pX, int* pY) {
     *pY -= vp_y;
     *pX *= sdl_window_scale.x;
     *pY *= sdl_window_scale.y;
+
+#if defined(DETHRACE_FIX_BUGS)
+    // In hires mode (640x480), the menus are still rendered at (320x240),
+    // so prescale the cursor coordinates accordingly.
+    *pX *= gGraf_specs[gGraf_data_index].phys_width;
+    *pX /= gGraf_specs[gReal_graf_data_index].phys_width;
+    *pY *= gGraf_specs[gGraf_data_index].phys_height;
+    *pY /= gGraf_specs[gReal_graf_data_index].phys_height;
+#endif
 }
 
 void Input_GetMouseButtons(int* pButton1, int* pButton2) {
diff --git a/test/DETHRACE/test_utility.c b/test/DETHRACE/test_utility.c
index 36c9642a..6bc35d0b 100644
--- a/test/DETHRACE/test_utility.c
+++ b/test/DETHRACE/test_utility.c
@@ -6,7 +6,7 @@
 
 void test_utility_EncodeLinex() {
     char buf[50];
-    gEncryption_method = 1;
+    gEncryption_method = 2;
     // first line of GENERAL.TXT, "@" prefix and line ending stripped
     char input[] = "\x29\x2a\x9c\x22\x61\x4d\x5e\x5f\x60\x34\x64\x57\x8d\x2b\x82\x7b\x33\x4c";
     strcpy(buf, input);
@@ -18,7 +18,7 @@ void test_utility_EncodeLinex() {
 
 void test_utility_DecodeLine2() {
     char buf[50];
-    gEncryption_method = 1;
+    gEncryption_method = 2;
     // first line of GENERAL.TXT, "@" prefix and line ending stripped
     char input[] = "\x29\x2a\x9c\x22\x61\x4d\x5e\x5f\x60\x34\x64\x57\x8d\x2b\x82\x7b\x33\x4c";
     strcpy(buf, input);
diff --git a/tools/decode_datatxt.py b/tools/decode_datatxt.py
index 6e597f6a..f81c83a7 100755
--- a/tools/decode_datatxt.py
+++ b/tools/decode_datatxt.py
@@ -13,43 +13,94 @@
 )
 
 
+class Byte:
+    def __init__(self, v: int):
+        self.v = v & 0xff
+
+    def __add__(self, v: int):
+        return Byte(self.v + v)
+
+    def __iadd__(self, v: "Byte"):
+        self.v = (self.v + v) & 0xff
+        return self
+
+    def __sub__(self, v: int):
+        return Byte(self.v - v)
+
+    def __isub__(self, v: "Byte"):
+        self.v = (self.v - v) & 0xff
+        return self
+
+    def __mod__(self, v: int):
+        return Byte(self.v % v)
+
+    def __imod__(self, v: int):
+        self.v %= v
+        return self
+
+    def __xor__(self, v: int):
+        return Byte(self.v ^ v)
+
+    def __ixor__(self, v: int):
+        self.v = (self.v ^ v) & 0xff
+        return self
+
+    def __and__(self, v: int):
+        return Byte(self.v & v)
+
+    def __iand__(self, v: int):
+        self.v = (self.v & v) & 0xff
+        return self
+
+    def __eq__(self, other):
+        if isinstance(other, Byte):
+            return self.v == other.v
+        elif isinstance(other, int):
+            return self.v == (other & 0xff)
+        raise ValueError(f"Object {other:r} of invalid type {type(other)}")
+
+
 def decode_line(line: bytes, method: int) -> str:
     line = line.rstrip(b"\r\n")
     key = LONG_KEY
-    seed = len(line) % 16
+    seed = len(line) % len(LONG_KEY)
     dline = bytearray(len(line))
     for i, c in enumerate(line):
-        if i >= 2:
-            if line[i - 1] == b'/' and line[i - 2] == b'/':
-                key = OTHER_LONG_KEY
+        b = Byte(c)
+        if dline[i - 2:i] == b'//':
+            key = OTHER_LONG_KEY
         if method == 1:
-            if c == ord(b'\t'):
-                c = 0x80
-            c -= 0x20
-            if not (c & 0x80):
-                c ^= key[seed]
-                c &= 0x7f
-                c += 0x20
+            if b == ord(b'\t'):
+                b = Byte(0x9f)
+
+            b -= 0x20
+            b ^= key[seed]
+            b &= 0x7f
+            b += 0x20
 
             seed += 7
-            seed %= 16
-            if c == 0x80:
-                c = ord(b'\t')
+            seed %= len(key)
+
+            if b == 0x9f:
+                b = Byte(ord(b'\t'))
         else:
-            if c == ord(b'\t'):
-                c = 0x9f
-            c -= 0x20
-            c ^= key[seed]
-            c &= 0x7f
-            c += 0x20
+            if b == ord(b'\t'):
+                b = Byte(0x80)
+
+            b -= 0x20
+            if (b & 0x80) == 0:
+                b ^= key[seed] & 0x7f
+            b += 0x20
 
             seed += 7
-            seed %= 16
-            if c == 0x9f:
-                c = ord(b'\t')
-        dline[i] = c
+            seed %= len(key)
+
+            if b == 0x80:
+                b = Byte(ord(b'\t'))
+        dline[i] = b.v
     return dline.decode(errors="replace")
 
+
 def main():
     parser = argparse.ArgumentParser(allow_abbrev=False, description="Decode a Carmageddon encoded file")
     parser.add_argument("file", metavar="FILE", nargs="?", help="input file (default=stdin)")