[What does Missing Required Level of Detail mean?]

Thanks for this thread... I was just getting a similiar thing exporting from 3ds Max.  I had an object exported from Revit, cleaned it up in Max, and then imported it.  Had to use Tools->RexetXForm, then Collapsed it. That made SL happy.

I had checked the log as mentioned above for more details, but it only had listed the framerate recently. Nothing related to the uplad.