What faction? I encountered it while playing Kingdom of Jerusalem and the Eastern Roman Empire, but there has to be others as well.

Error message?
20:22:45.703 [system.io] [warning] open: data/loading_screen/loading_bar.tga.dds is missing
20:22:45.703 [system.io] [warning] open: data/loading_screen/loading_logo.tga.dds is missing
20:22:47.296 [system.io] [warning] open: data/models_engine/textures/#fireball_tail2.texture is missing
20:22:47.296 [system.io] [warning] open: data/models_engine/textures/Torch.texture is missing
20:22:47.312 [system.io] [warning] open: data/loading_screen/loading_bar.tga.dds is missing
20:22:53.859 [system.io] [warning] open: data/descr_fire_texture_list.txt is missing
20:22:53.859 [system.rpt] [error] Medieval 2: Total War encountered an unspecified error and will now exit.

This happens right before you are fully loaded into a siege battle. There was another error with building fire, I added that .cas already but now I'm guessing one of these errors is the cause.

I can't find descr_fire_texture_list anywhere in list contents either.

Thanks,
Dylan