"Yes, here is what you should do:
Download the Brazil Demo (and install). Don't worry, you won't actually be using Brazil.
Set your renderer to Brazil
Use Neon and fool around with Global Illumination and Bounce numbers from Brazil…"
"THe issue is that light does not bounce, so only light that would hit the surface directly actually lights it. In all three of your example shots, the light source is above the roof that you are having issues with. The easiest solution is to…"