This is my fav game from the jam now. Just finished it. I will say a couple of the levels were a miss for me, but for most of the levels, they were great. They got a lot of things right. They were set up to lure the player into an assumption that would make the level look simple yet impossible. And I'm surprised at how many clever situations / "unique solutions" to be had from so few mechanics. For example that level where you have to look like a J, where you had to look for a shape that would work for all three "gates". Levels like that prevent the levels from feeling like different versions of each other. In other words, (for the most part) each level had its own new idea to communicate, which in my opinion should be the goal of any good puzzle game.
That being said, some of the levels lacked the above "simple yet seemingly impossible" setup with the "ah-ha!" moment as you challenge the right assumption. For some of the weaker levels, I just played it, and while I messed up and had to go back here and there, for the most part I never got "stumped" on anything. I just kind of did it and there were no epiphany moments or clever ideas. I think since there were a lot of levels, and especially since it's just a game jam, it may have been better to edit out the less clever levels, leaving only the best ones.
I'll also suggest that this game reaaaallly needs an undo button. It's really annoying to have to restart at the end of a level due to a careless mistake of not noticing something. I've made puzzle games and was reluctant to add one to my mine as well. But I think I realized that the best puzzle games shouldn't be made easier by an undo button; only less tedious / frustrating. The difficulty shouldn't come from executing without messing up, but rather from finding the clever solution. Once you have the solution, it should be easy to execute. I think a few of the levels in this game were more about the former than the ladder unfortunately.
One more suggestion: some levels looked intimidating at first, and I had no idea where to start, which is generally not good. I've had this problem in my creations too, it's hard to avoid.
Overall, I think this game has great potential to be expanded into a full release. If all the levels were as good as the best ones, and the scope / number of mechanics were expanded, this could totally be a really good full game. Great job :)