CombatAIFix – Fixes AI behavior in combat (for version 3.1).

Good afternoon. Could you please tell me if this mod is compatible with Heroes 5.5 RC15 beta 2? If so, what steps need to be taken to get the game running with these mods?

No, it is not compatible. This mod makes changes to the .exe file, and the 5.5 mod also makes changes. To get the mods to work together, you need to create an .exe file that combines the changes from both mods, but mods that modify the .exe file don't appear every day....