The elevator level does seem to have some bug and I will look into it after the jam is over :)
The restart and the respawn mechanic are different in this game. You can restart with R which resets the whole level whereas the respawn mechanic simple respawns the player blob to the spawn point... I was planning to make more levels utilising this mechanic but couldn't do so because of the time limit. Now that I think of it after submission, the respawn mechanic does seem a little weird so I will try and experiment with it later to see how it fits the game.
Some levels (especially the staircase one) are intended to be beaten in a way where you fit into tight hallways by fusing inside it although the squash/stretch animations make the collisions a bit inconsistent.
Thanks for the feedback :D