Thanks . Really the issue is just that Magic's support of 3D models is pretty basic: complex geometries may not be displayed properly, depending upon the format; pre-baked animation doesn't work at all (animation has to be done in Magic); and textures have to be saved with the original model (they can't be added in Magic later).
I'm hoping to expand 3D model support in the future, but I don't intend to develop an entire 3D engine from scratch so I'm not sure how far I will go with it.