I have it. It is super powerful, but there really isn't much documentation on how to use it, other than a brief overview and instructions to modify the existing demo code which comes with it. Matt is a genius to have put this together himself.

Sphere2 definitely requires a lot proficiency in c-script and shaders..

I bought it but don't really use it, mostly because there aren't really any tutorials and don't want to try to hack the demo code into my own.

I would -love- a good tutorial.

EDIT:

That light_update code fixed one of my problems with Sphere2, and now the outdoor level runs great. But when I launch the indoor level, it never loads-- just stays at the splash screen. Any ideas?