Classroom Scene from Vizdepot
If you haven't seen them, please visit them at www.Vizdepot.com
Vizdepot has a fun scene to play w/ KT and lighting a room using only the Sun & Sky.
you DON'T HAVE TO BE a member of Vizdepot you can with all their on (YOU MUST SIGN IN to view their .jpg examples, but I'll post the first one here for you... RENDERED IN MAX AND NOT RENDERED BY ME!)

I have Max at work now... here's the .obj. (only one mat.) and SketchUp file

- Blender preset (quad faces) (only one mat. in the file, sorry) hope you can material it up in Blender?
- DeepExploration format export from Max + tirangulated faces (only one mat. in the file, sorry)
(Autocad file format export from Max broken out into parts - to try importing w/ SU for materials)
- export (includes Max texture coords)
- V. 2009.0 for use w/ Revit, can be converted to other formats w/ some programs like Deep Exploration. (brings lights, but doesn't apparently bring Mray specific lights, converts them to nearest equivalent)
(in bite-size parts)
I was able to open the blender-compat. .obj version above into KT, but the normals were bad, and some smoothing was missing, and it's all one single mat... but you can set the diffuse on it to white and set sun & sky and render it.
So I started the diff. work of converting the ACAD into SketchUp and broke it into parts. If you can get fix the .skp file (normals, missing faces, etc) get the tables and chairs into components and share them back, it would be helpful. (And the radiators) thanks.