The achievements seems to be broken. When I finish the ritual at the start of the game, the achievement "Magic" is not unlocking. I've tried it at two different PC's.
Any ideas?

I'm having the same problem, though I got "The End?"

I just beat the whole game, and not a single achievement unlocked in Galaxy. Definitely broken. GOG Galaxy doesn't show a single achievement unlock amongst any of the 181 people I have on my GOG friend list in the past two years. It's possible that none of them have played in that long, but my guess is they've been broken for at least two years.

Broken game.
No setting to change monitor or go to windowed mode, can't play it.