Thanks for your feedback!
An undo button would be great, but it would require a lot of coding as I didn't planned it. So I'm unlikely to have the time during the jam.
Hey, to play new levels, I have to play all levels I completed before again. I suggest unlocking a few levels(like the ones where you introduce a new mechanic) in between and we can progress in the game from those levels too. I think that would help players who can't complete a level could also explore more and discover more puzzles. (maybe the third level).
I enjoyed playing again since you fixed the keyboard movement.
EDIT:completed again:)
I solved two levels with one collecting shard and the other jumping into water and the levels still completed. Was that intentional? cus I see a possibility where I don't have to jump into water.
Thanks for your interest.
Player progress resets every time I update the game due to a itch.io related problem when using playerprefs to store data. I'll work on a better solution after the jam.
On the next update I will add a "Skip level" button that appears when the player stays too long on the same level. It will prevent players from getting stuck.
The bug you encoutered was not intentional :(