i like how the movement is made - it's rather hard to manage the ships but i think on the sea it should be that way) it's part of the fun)
but levels are hard to read. some signs are misleading - like the red cross on an island: when i fisrt saw it I thought it meant something and i should go to it but it only wrecked my ship(
i didn't understand what those sings with arrows were about either and i didn't know you could shoot before i read it in the comments)
also the game is punishing because you die instantly and have to restart the game every time you thought you're doing what the game want you to - like this red cross or signs. i would always die whenever i tried to get to them and when i did - nothing happened
and it was a bit frustrating when camera moved with no contstraint to the ships and you couldn't see what's ahead
i think it would help the game so much if you'd make 1 or 2 simple basic levels where you'd explain most of the mechanics and techniques first) and if you'd give your ships like 2 or 4 lives before wrecking - that would be really cool)
i understand it's hard to make a game in 48 hours by youself when you're not a pro - i surely didn't manage to do that :) - but i hope my feedback will give you some info on what could have been more clear next time)
cheers)