I ran a test that involved creating a simple scene (scene1) with a single light. I used raytracing to render a frame. All worked well. After that, I created a new scene and referenced in the first scene (scene 1) then set up a single light and rendered it using raytracing. All worked well.

This now leads me to believe that the problem is not in the referencing but rather, something specific to the file that is doing the referencing. To test my theory, I went back to the "suspect" scene that is referencing the model scene. I turned off the referenced file (in the reference editor) then set up a simple scene, lit it and tried to render with raytracing. The calculations took a long time, as usual with raytracing but there were no shadows. The individual objects in the scene had shadows but the they did not cast shadows onto eachother or the floor. I checked the attibute editor to verify that all objects were set to cast and receive shadows... Everything looked ok.

I am out of my depths right now. I don't know why this is happening. The scene that is doing the referencing has all of the keyframe animation info for the scene. Maybe a possibility would be to export all of the keyframe info to a fresh file then reference the model file into it. I don't know how to do that or even if it is a reasonable scenario.

The reason I am referencing the model scene into another scene for animation is because I am still tweeking the model's paint job and skin weights. By doing it this way, all changes carry forward into the referencing scene.

Any thoughts?