Thank you for your nice comment :)
you are right, the body parts are a bit hard to see sometimes.
We thought the vent is to small for a hole body to fit. so you have to drop all the other parts. Also as a signal that you dont need the bodyparts you have on the next paths. Unfortunately we couldnt finish the feature to drop the parts on the ground and now you just lose them. We kinda missed to tell the player that they lose the parts then entering the vent...
Keeping the mouse button pressed to move is also a good idea. Maybe we can add that later. I dont know, Im not the programmer^^