I haven't encountered any game-breaking bugs. My game already had the 1.5.1 patch.
You lucky bugger. How about non-game breaking bugs? Could it be that there's someone who hasn't encountered any problems at all?
Even with the patch I've had the game breaking bug of the main plot line getting stuck in Cordon when the captured soldiers buddies didn't spawn in. And right now I might have another, I can't go to the Apogrom as if I do about 30 seconds after I arrive the game crashes, though right now that's just an annoyance as all I have to hand in there are side quests, but if I have to go back for the main plot I'm boned.
On top of that my faction war has ground to a halt as the squads who are meant to come and take the area I cleared are stuck in terrain, meaning the mission will never be completed and I can't go onto the next one.