The game is nice and I like the mood.
The camera is a bit fast for me, and the lack of a way to keep track of what you collected hurts the gameplay.
I could see this growing up to have more areas and challenges, but don't forget to ground your houses :P
You forgot to unlock the mouse in the end screen, and I find that FPS games are really hurt for not having a pause menu and not allowing the player to free the mouse other than alt-tabbing.
A visual indication of the scene limits would be nice too.