animated models are stored as separate mesh, skeleton, animation (using the same skeleton), texture, and material files, plus a physics body needed to be created, but there are easy video tutorials.
but all of these were generated automatically for me when I imported an animated ms3d model (except physics body which is one click).
really simple, and the only feature limitations is that no custom shaders can be created. and for 150 USD you get 2 complete game source code with MMO client/server codes.
and definitely good for a couple of purposes