I got to the exit area fine, I just couldn't see how to get a cube up there.
Ah, I see. The new version should make the final solution more apparent.
ADDENDUM: I just played Archie's map. Nice puzzle, and there are quite a few architectural eye-candies as well.
I do have two suggestions though. I thought the light bridge should be activated by default. There is no real purpose for the player to press the switch to turn it on permanentely. Besides, the switch just becomes a physical obstacle when the player walks back and forth between the chambers.
In fact, the light bridge can be replaced with a grill, which would serve the same purpose here. I cannot think of any other use of the light bridge in this puzzle.
In addition, the small room with all white panels is too bright. I suggest removing the observation room instance in there so the player isn't blinded by the light.