I was playing Level Omega-18 "True Elimination" where you are given 36 keys, 72 locks with 12 corridors so you have to choose correct pathways.
I noticed that after 4th corridor, you have to interact Blank Pink or Cyan Door to progress.
I found out that probably intended solution is collect all the keys from beginning and do not turn back.
But I managed to not collect pink key at the start, open Blank Pink Door, climb back to start using Cyan door and platforming, collect pink keys and continue onward.
I think this is very minor thing, but by narrowing the dropping area by 1 tile will make it impossible, since you will bonk the head to ceiling.