Thanks for the feedback! I agree that the 3C definetly needed more love. The Red door closing is not a bug, without spoiling too much, the pressure plate in that level is controlling both the red and blue door making the red one close while the blue one opens so you need to time it right with your loopie. :)
Just went back and had another go, managed to get all the way through this time. When I played the first time I viewed those switches as a half size red and blue switch next to each other on the ground (2 seperate ones) rather than one switch with 2 colours. Also, the movement of the doors as they move up could be a bit smoother as my eye is drawn to them quite a lot.
I like the idea of you not having enough characters so sometimes they have to perform double duty.