My PC can usually figure it out if I let it "wait for the program" per Window's 10 pop up when the game, freezes or lags prominently. I haven't taken a lot of turns but I have been alt-tabbing a lot to the discord application to ask a few questions and also participate in some good conversation. Aside from that I have a few internet tabs of Chrome open. 

auto-save 499.ctr

Turn 80 didn't seem lagged at all.

auto-save 500.ctr

Turn 81 started to lag considerably.