It's short, it works, it's beatable, so in many ways a success.

I opened all the doors and got the You've Won message but I didn't quite understand what was going on. I saw the aliens near the doors but they didn't move when I opened the door, so I didn't see the consequences.

Maybe it's on my part but I didn't get what was going on. I will give you one advice tho: you should normalize the character movement.