For jams, a web version is a real plus, , tried the windows build, first comment I have is please support different keyboard layouts (I don’t know how gamemaker manages it but at least add arrows then.
I had one projectile ennemy who ended my first run and on next runs I went through lots of floors without any ennemy.
Also, maybe find a way to generate your floors faster or while the level is playing to shorten loading times ;)