Am back. Found a few problems. For some reason, I can't change the walking keys, though the rest works. I also seem to be able to fire a seventh time if I hold the fire button. Not sure if you know about these or not, but I figured you might want a heads up.
I also managed to get myself stuck - There's a room that you can drop down into. I have a feeling the ice in front of the doorway is supposed to disappear, but otherwise I'm not sure. It's just after you enter the rooms - you take the side tunnel, and instead of jumping up to the top room, you drop down. I also managed to make the crouch mess up - instead of holding it down, I'd only tap it. This meant that there were a few areas where my head went into the ceiling, as the model didn't match where the ceiling was. Other than that, looking real nice. Keep up the good work.