Cool! :-)
Would be better if you could use WASD to move the character (especially for right-handed people like me (which most people are, I guess).
Definitely! I'll go back and implement this as well as fix any major bugs when I find time, but I'm currently swamped.
Also, the reason the door isn't opening is because the little alien dude is stuck against the wall up there. You should be able to continue if you jump high enough and shoot it. Sorry for the bug!