I can install (albeit just barely, as my disks are scratched beyond repair) and run the vanilla M2TW just fine, but when trying to install kingdoms, this issue makes both the Kingdoms expansion completely unplayable. The issue only appears either while the battle map is loading, or a few seconds after the battle map has loaded, never on the campaign map, like I have read some other user's have experienced. I have tryed many if not all of the supposed remedies I have seen on this board (update drivers, total un/reinstall, et cetera), and none have worked.
Here is where I think the problem lies. When updating M2TW, before the Kingdoms installation begins, the installer updates the game to version 1.02.001 with no issue, but when updating to version 1.03.000 it says,
"Error: invalid or missing target C:\Program Files\Sega\Medieval II Total War\packs\data_1.pack
Update could not be continued."