Resolving conflict with CtB (first pass)

As reported by RateLimited on Discord, IWDification fails when trying to make cosmetic patches to spells since the resources
are no longer from IWDification but from Check the Bodies. This is just a first pass to allow installation; a deeper dive
should follow to address warnings and/or other secondary issues.

iwdification/iwdspells/lib/cd_arcane_post.tpa

@@ -123,9 +123,10 @@ DEFINE_ACTION_FUNCTION cd_arcane_post BEGIN
   COPY_EXISTING ~decasta.itm~ ~override~
     LPF ALTER_EFFECT INT_VAR match_opcode = 8 parameter1 = ~0x00006400~ END // from 0/100/0 to 100/0/0
     LPF ALTER_EFFECT INT_VAR match_opcode = 215 opcode = 141 parameter2 = 1 END // from invoch
+    IF_EXISTS // if spell installed from elsewhere (ctb), this isn't here
 
- // Emotion spells: the projectiles should appear more similar to the small area of effect sparkle area gold projectiles (i.e. HOLD.pro).
- COPY_EXISTING ~idpro255.pro~ ~override~
+  // Emotion spells: the projectiles should appear more similar to the small area of effect sparkle area gold projectiles (i.e. HOLD.pro).
+  COPY_EXISTING ~idpro255.pro~ ~override~
                ~idpro407.pro~ ~override~
     WRITE_LONG  0x0c (THIS | BIT0) // add 'show sparks' flag
     WRITE_SHORT 0x28 4 // gold   
@@ -134,9 +135,11 @@ DEFINE_ACTION_FUNCTION cd_arcane_post BEGIN
   COPY_EXISTING ~dobone.itm~ ~override~
     LPF ALTER_EFFECT INT_VAR match_opcode = 215 opcode = 141 parameter2 = 1 END // from necroh
     LPF ALTER_EFFECT INT_VAR match_opcode =  61 parameter1 = ~0x785a3c00~  END // 60/90/120
+    IF_EXISTS // if spell installed from elsewhere (ctb), this isn't here
 
   // Lich Touch: LTOUCH.spl should be using necromancy/aqua SHEARTH plus accompanying glow and sound. Currently using IWD-style visuals. 
   COPY_EXISTING ~ltouch.spl~ ~override~
     LPF ALTER_EFFECT INT_VAR match_opcode = 215 opcode = 141 parameter2 = 1 END // from necroh
+    IF_EXISTS // if spell installed from elsewhere (ctb), this isn't here
 
 END