A really great puzzle game, especially the penultimate level, where you have to do everything in reverse it really makes the most of the whole system you've set up.
I found it a bit frustrating when I moved one character incorrectly and then had to replay the other character’s entire sequence before I could fix the first one. Being able to choose which character to control at the start of each loop should solve that problem, and I don’t think it would hurt the gameplay.