Hey, thanks for the compliments. All the credit for art goes to iDLELUKE :)
So what you need to do in the third level/room is use two boosts to reach the middle platform. Then stand in front of the spikes on the left, boost once and after a short delay start moving. This way, you will reach the upper carrot and fall to the switch which opens the door. Now use the last boost to complete the room.
If you start moving too late, you’ll get stuck on the ceiling and fall, as you said. If you move too early, you’ll run into the spikes directly before you.
Hope that helps.
Yeah, it’s perhaps a bit unorthodox to make a platformer go right to left. Glad you figured it out!