diff --git a/Graphics/Implicit/ExtOpenScad.hs b/Graphics/Implicit/ExtOpenScad.hs
index 0b6d53f0..ce33bcbe 100644
--- a/Graphics/Implicit/ExtOpenScad.hs
+++ b/Graphics/Implicit/ExtOpenScad.hs
@@ -22,19 +22,19 @@ import qualified System.Directory as Dir
 -- Small wrapper to handle parse errors, etc
 runOpenscad :: [Char] -> Either Parsec.ParseError (IO (VarLookup, [SymbolicObj2], [SymbolicObj3]))
 runOpenscad s =
-	let
-		initial =  defaultObjects
-		rearrange (_, (varlookup, ovals, _ , _ , _)) = (varlookup, obj2s, obj3s) where
-			(obj2s, obj3s, _ ) = divideObjs ovals
-	in case parseProgram "" s of
-		Left e -> Left e
-		Right sts -> Right
-			$ fmap rearrange
-			$ (\sts -> do
-				path <- Dir.getCurrentDirectory
-				State.runStateT sts (initial, [], path, (), () )
-			)
-			$ Monad.mapM_ runStatementI sts
+    let
+        initial =  defaultObjects
+        rearrange (_, (varlookup, ovals, _ , _ , _)) = (varlookup, obj2s, obj3s) where
+            (obj2s, obj3s, _ ) = divideObjs ovals
+    in case parseProgram "" s of
+        Left e -> Left e
+        Right sts -> Right
+            $ fmap rearrange
+            $ (\sts -> do
+                path <- Dir.getCurrentDirectory
+                State.runStateT sts (initial, [], path, (), () )
+            )
+            $ Monad.mapM_ runStatementI sts
 
 
 
diff --git a/Graphics/Implicit/ExtOpenScad/Util/OVal.hs b/Graphics/Implicit/ExtOpenScad/Util/OVal.hs
index b6db1407..bac03bfa 100644
--- a/Graphics/Implicit/ExtOpenScad/Util/OVal.hs
+++ b/Graphics/Implicit/ExtOpenScad/Util/OVal.hs
@@ -1,4 +1,8 @@
-{-# LANGUAGE OverlappingInstances, ViewPatterns, RankNTypes, ScopedTypeVariables, TypeSynonymInstances, FlexibleInstances #-}
+{-# LANGUAGE CPP #-}
+#if __GLASGOW_HASKELL__ < 710
+{-# LANGUAGE OverlappingInstances -#}
+#endif
+{-# LANGUAGE ViewPatterns, RankNTypes, ScopedTypeVariables, TypeSynonymInstances, FlexibleInstances #-}
 
 module Graphics.Implicit.ExtOpenScad.Util.OVal where
 
diff --git a/Graphics/Implicit/ObjectUtil/GetBox2.hs b/Graphics/Implicit/ObjectUtil/GetBox2.hs
index 464d0a9a..43ba9b16 100644
--- a/Graphics/Implicit/ObjectUtil/GetBox2.hs
+++ b/Graphics/Implicit/ObjectUtil/GetBox2.hs
@@ -114,12 +114,12 @@ getDist2 p (Translate2 v obj) = getDist2 (p ^+^ v) obj
 
 getDist2 p (Circle r) = magnitude p + r
 
+getDist2 p (PolygonR r points) = 
+    r + maximum [magnitude (p ^-^ p') | p' <- points]
+
 getDist2 (x,y) symbObj =
     let
         ((x1,y1), (x2,y2)) = getBox2 symbObj
     in
         sqrt ((max (abs (x1 - x)) (abs (x2 - x)))**2 + (max (abs (y1 - y)) (abs (y2 - y)))**2)
 
-getDist2 p (PolygonR r points) = 
-    r + maximum [magnitude (p ^-^ p') | p' <- points]
-
diff --git a/Graphics/Implicit/Primitives.hs b/Graphics/Implicit/Primitives.hs
index 5b7ad2b5..47977c2f 100644
--- a/Graphics/Implicit/Primitives.hs
+++ b/Graphics/Implicit/Primitives.hs
@@ -193,14 +193,14 @@ rotate3V = Rotate3V
 
 pack3 :: ℝ2 -> ℝ -> [SymbolicObj3] -> Maybe SymbolicObj3
 pack3 (dx, dy) sep objs = 
-	let
-		boxDropZ ((a,b,_),(d,e,_)) = ((a,b),(d,e))
-		withBoxes :: [(Box2, SymbolicObj3)]
-		withBoxes = map (\obj -> ( boxDropZ $ getBox3 obj, obj)) objs
-	in case pack ((0,0),(dx,dy)) sep withBoxes of
-			(a, []) -> Just $ union $ map (\((x,y),obj) -> translate (x,y,0) obj) a
-			_ -> Nothing
-				
+    let
+        boxDropZ ((a,b,_),(d,e,_)) = ((a,b),(d,e))
+        withBoxes :: [(Box2, SymbolicObj3)]
+        withBoxes = map (\obj -> ( boxDropZ $ getBox3 obj, obj)) objs
+    in case pack ((0,0),(dx,dy)) sep withBoxes of
+            (a, []) -> Just $ union $ map (\((x,y),obj) -> translate (x,y,0) obj) a
+            _ -> Nothing
+                
 
 -- 2D operations
 
@@ -210,10 +210,10 @@ rotate = Rotate2
 
 pack2 :: ℝ2 -> ℝ -> [SymbolicObj2] -> Maybe SymbolicObj2
 pack2 (dx, dy) sep objs = 
-	let
-		withBoxes :: [(Box2, SymbolicObj2)]
-		withBoxes = map (\obj -> ( getBox2 obj, obj)) objs
-	in case pack ((0,0),(dx,dy)) sep withBoxes of
-			(a, []) -> Just $ union $ map (\((x,y),obj) -> translate (x,y) obj) a
-			_ -> Nothing
+    let
+        withBoxes :: [(Box2, SymbolicObj2)]
+        withBoxes = map (\obj -> ( getBox2 obj, obj)) objs
+    in case pack ((0,0),(dx,dy)) sep withBoxes of
+            (a, []) -> Just $ union $ map (\((x,y),obj) -> translate (x,y) obj) a
+            _ -> Nothing
 
diff --git a/implicit.cabal b/implicit.cabal
index 8292e83c..fc088bd9 100644
--- a/implicit.cabal
+++ b/implicit.cabal
@@ -39,7 +39,6 @@ Library
         
     ghc-options:
         -O2 -optc-O3
-        -threaded
         -rtsopts
         -funfolding-use-threshold=16 
         -fspec-constr-count=10