You can check Pixel Camera box in your material to allow Vertex and Transform to work, but inorder for that to work, you must have a Reflection Node connecting into your Transform. Either Mutiply/Add your Reflection to whatever is entering your Transform, or subtract reflection by itself and again, Multiply/Add to whatever…
So, I've been trying to export vertex colors on my mesh using FBX into UDK, so I can use a vertex color node in the material editor to effectively paint bricks different colors on my mesh. It was working for a bit, I think it stopped working when I hooked up my cubemap reflections, but I can't seem to get it working again…