Yeah, I had trouble with each item having a random color for diffuse.  Most didn't have a preview material, so I thought it was trying to combine the two.  A couple had preview mats and did it anyway.

I made a "theschell" textures folder, and imported the OBJs as props (uncheck all options).  None of them had moving parts, so that made sense anyway.  Just a little work, and everything performs fine.  Like you said, worth the trouble.

John