Cool, original concept. The lighting thing was cool, but as you said, processor intensive. So it was a bit sluggish for me (i7-2639QM 2.0 Ghz laptop, 6GB ram running win7). Overall it was fun to move the lights around and try to get from room to room without losing my "sanity". The controls were a bit touchy when moving boxes and lights around, so it was hard to get them exactly where I wanted, and even once I got the boxes on the switches, if I came back into the room it would reset, so I'd have to replace the boxes. I see why the lights reset, but it'd be nice to keep the boxes on the switches (assuming that's the winning case). I admit I didn't have the patience to try and solve the whole thing - sorry! Couldn't figure out how to get light into one of the areas.
Overall - really original and fun. Good job!