Thank you for the feedback! I'll change the door after the jam ends. In the door section, the player needs to be near the door for the pieces to be interactable. When you enter the trigger, the pieces change their color and when you press them, they make a sound (and their color changes again). Also, it's not needed to go away and reenter the trigger if you input any wrong answer, the pieces will reset automatically. About the relation with the theme, I'm afraid the big part of it is after that door.
I would appreciate if you tried again getting as close as you can to the door, so that you can see the whole story. I think your opinion will change.