This was a fun game. It took a while for me to understand the different alien settings (mostly because I didn't realize that you could enter doors for the blue one and the purple one only lasted a few seconds).
I think it would be good if the player were able to enter doors while moving (rather than having to stop pressing the move keys to be able to enter them). I also feel like having a timer show up on the screen for the purple alien setting would be beneficial, so the player knows right from the get-go that it's a timed event.
Great work!