Ockham...  No luck.  I tried both importing with flip normals on, flipping the normals in the group editor, and stripping the normals out of the OBJ file.  Same result.

Also the example with the 2 cylinders is exactly the same as the first which rendered black except for having two of the same object.

There seems to be something about the single object mesh that I exported from Carrara that is puzzling Firefly.  I've stripped the meshes down to the basics and still get this result.  The only difference I'm seeing is the scaling between the two programs, and I've tried scaling it down before exporting and scaling on importing all with the same result.

Any other ideas?

Thanks!!