I got the Smart walls from an old AUM, I am not sure where, but all it did was turn invisible on and off. I think it's an issue with my video drivers, not the code, because models with an alpha channel have z-fighting issues, the same as in Maya with models there who have an alpha texture in their channel.

Now that that's solved, any idea how to fix the alpha problem?

Thank you George for such an immensely useful newsletter. Between the documentation and AUM I'm able to do anything I can imagine.