It doesn't happen every time, but lately, I've been having problems with the game freezing up when I change speeds. The cursor doesn't disappear and the animations (plum bob spinning, tree branches moving) continue playing, but the game itself freezes. I can still move the cursor, but I can't click on anything. It usually happens when I go from speed 1 to speed 3--for example, when the last Sim on the lot goes to bed and it automatically speeds up while they sleep. I usually give it a few minutes to see if it'll solve itself, but it seldom does (I left it open and running for 20+ minutes once, didn't resolve itself). My last several sessions have ended with me force quitting the game through Task Manager, and I keep loosing entire in-game days of progress.

I'm running TS3 through Steam on Windows 8.2, if that makes a difference.

Yeah, I've had that problem too, but I haven't had to force it to shut down more than once. It gets really annoying, because you have no idea if it will fix itself or if you will have to lose all of that progress. I'm running Sims 3 on a Windows 8.1 Laptop.

Well, I've been saving every 12 in-game hours, and I haven't had it freeze up for more than a few seconds. Not sure if the saving's doing the trick, or if I've just been lucky.