I'm not sure if clay rendering takes into account materials with internal/external volumes assigned. Here is a result after a few minutes of clay rendering.. It seems there should be no color other then clay, but I see blue and purple all over. Also, does clay render take portals into account?
I've also noticed that displace modifiers don't seem to work unless you apply it to the mesh pre-export. This is kind of a pain because then it is permanently deformed. The cubes in this picture appear to be intersected by a flat plane, but it should really have displacement on it.
