The game hasn't changed much since the last time, as informed by the first comment, but I do have a couple of notes.
I think that doing the "a door opened somewhere" is fine when there's a single closed door in the stage but if the maps are going to get more complex this may become a problem in the future. Cables going from the button to the door could be a nice, organic solution and contribute to the room decor as an added bonus.
I experienced no performance issues during the second stage, and I'm playing in a toaster.
I also found the floating headlight someone else already reported. The enemy is dead but it's still doing the animations. However, it can't move.
I'm afraid I couldn't tell if it's dealing damage or not because I had no health left.
Keep up the good work.