I would suggest a back wall behind the camera IF you have anything reflective such as glass or mirrors in your image on the visible walls. A reflection of infinite plane and sky is just not right! These details do count. I usually don't bother to disable sunlight, just employ blocking planes or large flat cubes. that way, when i have a window to look out of I still have the sun to play with. Good luck, have fun and as MadDog says, pop back in and let us see.

Pass no temptation lightly by, for one never knows when it may pass again!