Thanks for the feedback!
Regarding the character controls: Fair enough. I think the controls in normal gravity worked well, but we ran out of time to fine-tune the zero-gravity movement.
Regarding the theme: The idea is that you escape from a deep cave, but the idea was lost a bit since the level became more horizontal than vertical. While working on the game (and already having the idea of an astronaut in a cave), I thought that "deep space" would fit as well, but that was not original intent. :)