I've encountered a CTD, which occurs repeatedly. I'm playing as Hayasdan, and fighting the Seleucids in the province where the Tigris and Euphrates flow into the Persian Gulf (sorry forget the name, but historical Sumeria). The fight autoresolves fine, but when i try to fight on the battlemap, it loads partially and then crashes with the following message:

Rome: Total War
Generic Error:
Failed to find texture 'eb/data/models_unit/textures/celtic_heavy_infantry2.tga.psd'

I went back and checked: there is no celtic unit on either side. Strange. Ive run into this problem a few other times in the same province, since then. Hope this helps.