Thanks for playing! I'm choosing which side to activate by raycasting from the center of the camera to the box. I supposed I could see how close to the center of the box face it hits and just disable movement if too far away, like when you are looking at an edge. I'm not sure this would be comfortable either though, because there are a lot of times when you might want to intentionally view it close to the edge to see how you are affecting both sides. I don't know; I may have to play around with it later and see what works.
I wanted to add an undo feature. I just didn't have time for it. I might add that once the games are unlocked.