Hmm, I'm experiencing some weird results. it looks like the world geometry may be lit correctly, but my static prop models in the 3d skybox are not. May be a source engine bug. Will look into it further.
I moved to another thread because it's probably a different issue.
What are your origin settings for the model? How are you creating the skybox? Are you using the WW 3D skybox functions? If so, how are all the components set up?
I've attached an image of the problem. It looks like its being lit from the side, which is why I posted that original post about the light angles. But I have actually noclipped into the skybox and I think something else is going on that's difficult to describe. I'll try to post a video soon. Regardless, it goes away if I go into hammer, and without changing anything, recompile from there. Its almost like hammer is silently correcting something in the vmt. Or possibly the render settings are different...
I haven't tried without the skybox model, but I imagine that it would do the same in non-skybox land. I'm using the normal 3d skybox stuff, no leaks.