I think I have an idea on what level You are referencing to. I might not have introduced the full mechanic of the slime properly in this game. Actually, You can jump over those slimes to gain a jump boost effect! This allows You to jump higher than you normally can, it's enough to let you reach the tall cliff on the right side of the level!
Also, that is an interesting glitch that You found. Is that has anything to do with the slime perhaps? Would definitely try to find and replicate it on My own and fix it.
I will also definitely overhaul the control mechanics and add a reset button later for a full version to make My game a generally more enjoyable experience. Thanks for giving a feedback! I'm glad that You liked the music I made for the game!