Ough :( I'm sorry, I haven't been able to figure out WHY it happens, yet ¬¬ I did manage to have a few playthroughs without issues when I took things slowly but maybe it's not buggy in that regard. Puzzlescript didn't inform me of any errors (concerning this issue) so I must have screwed up the logic somewhere. Thanks for giving it a shot. :)
If it makes it easier to hunt down, I can repeat the issue in the second level by trying to activate the door-opening-thing from one particular point. If you stand in the spot below, face up and then input X-UP-X-UP, you get the activation sound but the door doesn't open.
EDIT:
Yeah, there's definitely something weird going on with where you're standing. In the original problem area there's only two tiles you can stand on to activate the door. On one it works and on the other it doesn't:
