I'm just testing a render without the small plane on the top of the room.. meaning with only one emitting mesh - and it's still not working.

Another problem: After fixingthe last problem and reading the great manual :D I got another problem.. An object with correct normals doesn't emit although it's material should. http://psprince2.ps.funpic.de/wip/blender/doesntemit.png It's Lambert like the very small emitting rectangle at the top of ...

I think you need to change the "Env Type" from "Map" to "SunSky" again in the Export-plugin's buttons.

zuegs was right. I turned off the RayMirror in the materials and it worked! Thanks!

Textures don't matter. (The shelves got a texture, too and it's not making them not beeing there.)
I flipped the normals already.. they are going to up. Normally I could see them.
And I am using Indigo_05.

http://psprince2.ps.funpic.de/wip/blender/im1157669049.png The strange thing: the floor in that image is no black as you can see in the blend file.. but indigo is rendering it simply black as if it's not there. Here is a 7z-File containing a blend: http://psprince2.ps.funpic.de/wip/blender/dasklein...