Just to be clear on yellow/green comparison, here, I've added an RGB 255,255,0 square to the images with Paint.NET. This square is yellow and walls are greenish (according to my wife, and that is the most important judgement [:)])

Well that's because you're adding a pure 255,255,0 square while the yellow rendered by SH3D is shadowed, but if you use a program which let you take the colour from a pixel and see the values you'll find that it's using the same (or almost the same) values for RG and 0 for B, but of course these RG value is lower so it looks darker, but still yellow.

To me it look right, but if you (or your wife, [:p]) don't like that way is your preference of course.

Anyway, forgot about the "one light on each compartment" solution, as I tried myself and it doesn't look right. But then I tried something which may work (not sure because I tried with a simple scene and it may look wrong with a complex one). The thing is as simple as take the "flashlight" object put it at mid elevation just in front of the virtual visitor (close enough so it cannot be seen) pointing forward to where the visitor is looking at, and with the light at 100% (you may adjust it lower if it's too bright).