I gotta admit, it was worth making it just to listen to your frustration.
I gave myself a super tight timeline to finish this game. It was one of those "lets do a small project to release something" projects, as a bream from a larger one.
Saving was considered between stages, particularly after the boss battles (there are 2.) At the same time, if a player has the option to just repeat the puzzle instantly it becomes incredibly easy. The game is designed for the "Dark Souls on hard mode for puzzles" type of players, but it is admittedly, not in a polished state - which would include saves.
I believe I did go back and add some form of saving as well as some bug fixes at some point, but never uploaded it. Not even sure if I still have the original file.