Let me know if I'm wrong, but you want to assign 12 separate textures to one mesh? This means you'll need to have a multi-sub object material with 12 slots, one for each texture. When you plug all 12 textures into each of the materials, go to the mesh and assign the same number to the specific element/object.
I have a custom helicopter model (huey) that was in GTA and I am trying to prepare it for crysis. I am using max 2012 and have gone into the material slate editor and replaced the GTA multi subobjects with standard subobjects. The texture on the helo remained the same because I used the same bitmaps. I am able to export…