It's good, but it lacks in the communication area. The controls should have been put somewhere in the game, because at first I didn't look at the screenshots here and had to button-mash to find out how to dive. Same thing with moving to another level, I only managed to get to the second level my moving randomly off the map.
On the other hand I liked the start screen and the 3D models were well done. The concept of the game design was accurately planned, so I gave you 5 stars in 'theme'. I'm sorry that you guys didn't get to polishing the user experience, but it's a nice submission overall... :)