thank you for your feedback! The pushable boxes can be pushed more than once, unless you somehow triggered a bug i don't know about. They're meant to trigger the pressure plates until you learn you can discard keys to weigh them down.
The extra movement keys were probably an accident, i didn't have much time to playtest so if I was able to solve a room, I put it in the game. There's probably tons of solutions i didnt know about.
Thank you for the feedback in the tutorial levels! I was trying to go for what portal did by making you learn by forcing you to use something.
Thanks!