I have 4.0, and it seemed to be working fine until I imported a Studio 3DS file, I can choose the material I like for the object, it show initially show's up in the nano preview window and I can use the spray render can to render one time maybe even several times, but the first time I do an actual render I loose my materials? I'll go back into the material lib for an object it will let me pick the material ,but at that point the nano preview window doesn't show the new material.