Has the bug whereby primary culture bureaucrats would never appear in colonies (thus meaning some colonies could never be promoted to states) been fixed? I'm aware that there was a Bureaucrat Assimilator Tool made some time ago, but I'm unsure as to whether or not it'll be necessary after the forthcoming patch. For what it's worth, I'd be very grateful if somebody could explain how to remedy the bug in 1.2 saved games (I know you can edit demote_migrants to no in bureaucrats.txt, but that only works for new games, and the aforementioned tool doesn't work for 1.2).
Yes, this is solved in 1.3. You will still need to get some primary culture pops to the state to start with, after which there will be assimilation towards the primary culture bureaucrats. You do need to keep an eye on it though as you can often end up with your bureaucrats demoting out of existence.