I'm also getting a hang every turn with the "Building Ships" popup showing. (Reported in-game)
The game can be saved and reloaded but the same issue occurs at the end of the next turn. It may not be relevant but I always get an event pop-up wheh I reload the saved game
This is with an existing pre RP3 saved game
I also think everyone has too much money - I've blockaded the Russians for some time and they still have +7% growth and 765,000,000 in their naval budget
I've since started a new game and am not seeing the hang