My high score was 476 seconds. But that was on my 8th try or so xD I only got about 800 seconds on my fifth try.
Good walkthrough, but what do you mean by 'DOES NOT NEED TO CLICK TO FIRE'? As far as I can tell you don't need to hold down the spacebar in order for anything to fire. =P
I only wish a sandbox mode would unlock afterwards with infinite enemies until you quit and infinite amounts of new parts that are allowed on the ship (I mean, 12 is a little low. Isn't it? xD)