This game looks pretty polished! I think this executes the "each button only once"-idea pretty well, there are just two things I did not enjoy too much:
- You need to hold the button. This makes some levels tedious since you held the button a tiny bit too long or too short and ended up on the wrong space. Simply marking off keys when you change directions would also work, while making this game accessible for people with tremors, who might not be able to hold a key down.
- The conveyorbelts. They did not move me tile by tile, and made getting off at precise points really hard. Also I think you messed up the level order on them, since the easy "explainy" level came after the harder one, but that stuff happens.
All in all, I enjoyed this game a lot! Great job!