First off, the difficulty is great, i unlocked all but one ship before I won (though I got close a couple times) and the difficulty makes winning feel like a real accomplishment, but isn't too hard. I did encounter a bug in the game I won. In the last sector the exit point has 3 stations, I destroyed one but had to jump away, I came back and got the second to about 1/2 to 1/4 health before having to leave to repair. When I returned only the third remained. The damaged one had just gone. I definitely didn't kill it, but when I destroyed the third I still won. Did the station self destruct?