Lighting issue on brush

I hate to start a new thread on this because I'm thinking there already is one and this is a simple fix, but I am at work so I cant look around to long. I added a large brush to a level in the GOW editor and then added a skylight to the scene. the light only effects  the center portion of the brush and I cant figure out why. Also I think the light is effecting assets on the "inside of my level" not just the courtyard it was intended too.