Lusted reported that the map_regions.tga apparently can contain some errors that the game tolerates. The game then creates a corrected_regions.tga that presumably has corrected these errors. One would think that the game would then use the corrected one, but apparently not, as since replacing the file, no post-battle CTDs ever occured in the mod in question.

The issue of the OP is part of the frequent issues, BTW.