First off, very clever to use the string as a unique game play mechanic! I grid based puzzlers, especially the ones where you can't return to where you've been before. The puzzles were good (loved the switches), and collecting the children gave you a reason not the beeline to the exit. Unfortunately, only qualm, was it ended up being frustrating that you needed to press the key every time, waiting to fully enter the next square; I also found it to be unresponsive at times.