If you wan't a model cast shadows in 3DGS you have to set the "shadow" flag on ( right click the model > properties ) And note that shadows for models work only in pro and comm version if I'm correct.

All models show up as wireframes in WED.

And about the model texture... hmm... If I'm correct you should just go to the skin editor in med and open a new skin. Does the skin show up in med? ( If you wan't to see a textured model in med you have to set the 3D view to show textures )

If this doesn't help you could take a quick look at the manual...