Got there eventually. Here are my thoughts:
It's a very interesting take on the Sokoban genre, I liked the multiple realizations you have as you begin to discover the mechanics at play. The difficulty is a notable factor, I think this can come in part from the lack of indication of progress, which is in part helped by the checkpoints, but the comments made me worried that a checkpoint would put me in an impossible position, even though I eventually finished. There was a bit of jittering when opening rooms inside themselves, but nothing that really affected gameplay. I did like the development of multiple sub-objectives on the way to the main objective; to reach the treasure you need to unlock this door, which has a door that is unlocked by this key, which needs to be rescued from this room, and so on, which is a nesting of challenges thematically liked to the mechanics of this game, which is interesting. The graphics are neat and functional, simple always works for a jam title, and the keys had a nice bit of personality to their design, especially when you could have gotten away with making them delineated by color.
Overall, a really solid entry for a game jam, I'll look forward to future work from this team.