Posts from RTF is a global modification that replaces all towns in the game.

There would be too many dogs then))

Come on, that would be a great dog-themed unit lineup:
Warrior Dog / Biter Dog / Chopper Dog
Dogmancer / Dogwarlock / Dogwizard
:D

What if we made the caster a Gnoll as well?

Bad idea. There will be 2 lizards, 2 gnolls, and only 3 other swamp creatures... it's not very good.

I have an idea to make the caster some kind of human shaman/druid (like some mages found refuge among the lizards and gnolls).

The idea is questionable, but there should be a caster.

We could make the caster some kind of swamp spirit (it's nonsense, but... maybe it will work?)

We need models of severed legs, but we don't have any, so we're using what we have.

Could you please tell me what format you need the detached legs in? If I provide you with Rakshasa legs in 3DS or OBJ format, will you be able to use them?

Unfortunately, I can't export models into the game; the editor always gives an error:( so it doesn't matter what format it is if I can't get them into the game.

Would it work to take a Rakshasa model with legs and hide everything except the legs with a transparent texture? (I think I've seen something like that before)

Unfortunately, I can't export models into the game; the editor always gives an error, so it doesn't matter what format they are if I can't get them into the game.

Oh, well, I can export them. I don't know how to create and process them, but I can export them. And I can give them to you as an archive with the models.
And I thought you were the one exporting them... How do you manage without that? Do you just work with the animations? Or am I missing something?