My friends and I launched the first combat rocket and received achievements as if we had passed the game, although the rocket had not yet been studied and built. Is there any way to fix this?

That's strange, I've actively blocked the rocket-launch-victory in my script (game.set_game_state{game_finished=false, player_won=false}).
Sorry for the inconvenience.

Did you just receive the achivement or did you get the victory message aswell?
To be honest, I have no clue how to handle achievements at all - I'll see if I can do something about that as soon as possible.

I've been able to reproduce the problem. I hope this didn't affect too many players until now in a bad way.
I'll fix it as soon as possible, maybe I can take a look at space exploration since they must have done the same with their rocket silos.

Thanks for your bug-report!