The 2nd Core mystery

[TylerX5]

I don't have the technical solution that you're looking for, but I will give you the advice that has been given over at the Hyrule Total War thread. For speeding up turn times (on a non-steam version) install the main game in a directory that has minimal characters in the address. So for example "C:\Program Files (x86)\MTW\mods\EB" (32 character) should load turns much faster than "C:\Program Files (x86)\Steam\steamapps\common\Medieval II Total War\mods\EB" (70 characters). The way TW games load for things on the campaign map each character adds a byte to be processed, which adds up quickly during AI turns where a lot of things need to be loaded quickly. I think I also heard that M2TW will crash if the address exceeds a certain number of characters (byte processing limit?), so doing this may help your stability too.