Is the relevant discussion over in the octane forum in a private thread for registered beta testers only or something? I couldn't find it when I searched.

Just going by what I've seen here, I agree with Michael's assertion that the vertex normals aren't being handled correctly. I don't like that example Radiance gave with the sphere from blender. It sounds like he just selected a few faces, flipped them, and exported. Seeing that the faces are messed up in Octane doesn't prove anything about how the vertex normals are being handled, since the winding order of the vertices in the face definitions would also have changed. Octane could very well still be just averaging face normals. I just can't see the usefulness in that example.