If you have the original 3D files, it’s pretty much a drag-and-drop procedure. The converter tool will create the msh and msh.blob files for you, almost regardless of what input files you use.
It supports .obj, .3ds, .blend, .lwo, collada, and probably .fbx too..
I’m tinkering with a tutorial, but I need to iron out some issues I don’t understand yet.