It's because the DX11 renderer turns negative pixel colors into that. You can just make a postprocess material that clamps the min value to 0 and add it to your PPChain.
WOW, dudes, thanks you for all.. o.0 this world is much bigger than I imagined. Thank you, but for the momment I will start with the actual systems. :)
https://dl.dropboxusercontent.com/s/pln4c7w1rw0w9nx/twinkie_scene.mp4?dl=0 Getting close to done I think but I need to get some really good feedback on it first
Couple tuts http://www.moddb.com/games/cc-renegade/tutorials/lightmap-tutorial (except don't set Flatten Map spacing to 0!) http://www.translucency.com/araya/