I'm not sure whats happening here but all the interior walls are rendering dark (black).
Even when using the design wizard. Any help?
Just wondering if maybe this is rendered using Advanced?
Basic render is best for Exterior views, which this angle is, so if you try that it should be OK (see first image below).
With Advanced render, the interior walls are expecting artificial light or sunlight through windows. If you were to use your model as in your image and move the camera BELOW ceiling level and INSIDE the walls, the room walls would still be black (although you would see the sky above), but if you had a window in the wall, they would light up accordingly. In Advanced, light will not come through the open roof. If you had artificial lights these would also illuminate the walls. In my second image you will see I have used artificial lights with Advanced render but the sun is turned off - that is necessary for artificial interior lights to work.
EDIT: I did not notice at first you had posted the BLD file too so I have now done a Basic and Advanced render. In the Advanced you will see the illumination is by the interior lights and the second Advanced with the sun off.
Hope that helps.
Let me know how it goes.
Allan
an alternative, with lots of lighting control, is to export the TFP as a model like .3ds .obj or .dxf and import that to a different 3D program, adjust textures as needed, and render with a program that uses lights properly (not the TFP constraints).