The good points:
I like the stars, they look great.
The ship designs are really cool.
It has a good side scrolling atmosphere.
The dialog system was a nice touch.
You have done a lot with a very simple system.
It was nice to see expression controllers being used.
The animation of the ship as it moves up and down, tilting was a nice touch.
At first I couldn’t start the game. It is setup so the first active scene is “background” I started by choosing one of the scenes randomly.
It seemed very difficult, I had to do the same difficult move again and again. Being able to choose when to shoot would have made that less annoying.
Everyone moved to the top of the screen where I couldn’t get at them easily. I also couldn’t see the bosses health bar because it’s off the screen.
Although there was music in the file it never played when I was going through the game. When is it supposed to play?
It was nice to have two different weapons, but the second one didn’t seem to be better than the first, despite seeming to fire slower. Maybe I missed something.
Overall I think it is a great game for just a week’s work, it reminds me of games I used to play when I was a kid.
If you were going to improve it I’d suggest more diverse weapons which you can choose when to shoot, being able to move forward and back on the screen as well as up and down, and some pickups like new weapons, armor or extra lives to give the player some incentive to move around the screen a bit more.
Anyway, great work, and good luck with the competition!