Ah, I wish I could use something like this for all animal-men, but I think the game will crash automatically, while merging all the graphic files. Mifki explained it to me here:
The limits question is more important. There's no fixed number, it depends on graphics card used. I think all currently used cards should support texture size 4096x4096 or at least 2048x2048. This gives 64 512x512 sheets or at least 16 sheets. It may seem ok then, but this also includes all creature graphics, so I really need to find a way to split tiles into several GPU textures and not worry about limits anymore.
Summary: All graphic tiles have to fit into one large, 4096x4096 png.
If we add just military professions to the 200 animal-people and other intelligent humanoids, that's 24*200*32px. With some professions to cover the visitors, scholars, performers, etc, lets make it 35 extra sprites per creature.
35*200= 7000 sprites. With creature transparency, 14000, because of the -bg files. With some good templates thats doable, but would crash. I alread have 10x 512x512 tilesets in data/art, and the large procedual sets for Titans, Demons, Nightcreatures and FBs are 1024x832, of which there are 4.
Overall I think there is enough space left for about 4000-5000 sprites. That's guess-work, but an educated guess.
tl;dr: Vordak, I/we/you can't do full spritesheets for all animal men. Only a few selected professions. I thought about 4: Melee, Ranged, Scholar, Performer. That's 1600 sprites in total. (200 creatures * 4 = 800. Times two for the -bg files) That's well within the limits of TWBT.