The audio is very impressive, you managed to set a really nice ambiance with so little! Graphic-wise. Well… you spoiled us with your previous two entries, it's not as good! But still get full points on presentation!
In term of gameplay. the gunning gets very repetitive. Especially with the slipperiness and the absolute lack of air control, it's just not fun moving around. Also considering how long it takes to respawn in a certain later level if you slip (which is very easy to do). The non-gunning parts were a bit puzzling, I think myself fairly detail-oriented, but it took me a lot of searching on some of the clock sequences.