most likely not. Volga bulgaria has the volga bulgars that are muslim in XL - the russian provinces get the russian factions and Livonia goes pagan as it should be - these are typcal changes and not a problem - the problem is when a province is used in another part of the map - say Livonia was turned into Murcia in Spain - then Livonia remains Livonia for the engine and the modder changes the name in the text but the engine still counts it as Livonia. If then a historical hardcoded message makes a change in that province that is not compatible with the new culture you get the ctd.

What about installation? Did you had any other mods installed previously? If you try to reinstal the game and then the mod- could it be something like that?