I have been playing a new game with the 1.83 Opt-In without a problem until one of the races that was at war with another race decided to surrender to me. At the end of that turn, the game hung when I clicked the Turn button. I could do everything, but the turn wouldn't progress. I saved the game and reloaded it. The game still hung when I clicked the Turn button. I did some experimenting and found ways to cause the game to hang or not hang, depending on what I did with a certain ship I acquired from the surrendering race. I also found a way to end the hang by moving certain ships while the game was hung.
Submitted saves and detailed information on Ticket #RME-685-36131.