Btw, now we are talking about it, I could also see this being a nice 2-player co-op concept. With 2 people it can help in both puzzle mechanics and player execution.
Oh and one more other feedback is that I think even though you color-coded the projectors, they were still really hard to differentiate (the color are not bright and not immediately obvious), so I spent a lot of time at first trying to turn on and off the different projectors just to remember the layout, and it took me until the end before I can kinda remember which one turns on what.