hoggy
I replied to your chariot thread some time ago, but I guess you didn't see it since it was a few days after you posted your question.

But yes, CAS files do have a link to a texture. Just open a CAS file with Notepad and you will see between the garbage something like: \textures\wotr_squire.tga

I noticed this once I made new strategic pieces, you do not assign the textures in a text file, instead the game knows which texture to use by looking into the CAS file. My guess is that the same counts for chariots.