Low: Work around OOS caused by [advancefrom]

Cleaner Alternative: not allowing the advancement

data/campaigns/Legend_of_Wesmere/_main.cfg

@@ -28,6 +28,9 @@
 #endif
 
 [campaign]
+    # "extra_defines" cause OOS errors if used to change unit types (e.g. their advancements)
+    # Using event below instead to change advancement. Though players won't that they can advance to this unit.
+    # leaving extra define so it looks still right from the hosts perspective.
     extra_defines=ENABLE_DWARVISH_RUNESMITH
     id=LOW
     define=CAMPAIGN_LOW
@@ -56,6 +59,20 @@
     {CAMPAIGN_DIFFICULTY NORMAL "units/elves-wood/lord.png~RC(magenta>brown)" ( _ "Lord") ( _ "Normal")} {DEFAULT_DIFFICULTY}
     {CAMPAIGN_DIFFICULTY HARD   "units/elves-wood/high-lord.png~RC(magenta>brown)" ( _ "High Lord") ( _ "Challenging")}
 
+    [event]
+        name=unit placed
+        [filter]
+            type=Dwarvish Fighter
+        [/filter]
+
+        [modify_unit]
+            [filter]
+                id=$unit.id
+            [/filter]
+            advances_to=Dwarvish Steelclad,Dwarvish Runesmith
+        [/modify_unit]
+    [/event]
+
     [about]
         title= _ "Creator and Lead Designer"
         [entry]