@jazzmiint Your Mac's hardware isn't all that powerful, but a number of people are able to play on this laptop or similar ones. Others have the same experience as you're describing. I'm not really sure what the difference is, especially considering how standardized the builds are and that the simple explanations (heat, other apps running in the background) haven't been a problem for at least some affected people.
Anyway, you can try to cover everything all at once. First of all, put the laptop on a hard flat surface (like a desk) so it will be able to cool itself properly. Restart the computer, and don't open any apps. Move the Sims 3 folder in Documents > Electronic Arts to the desktop. Sign into Origin and put it in offline mode, then disable the laptop's wifi so you're entirely offline. Launch the game, load a new save in Sunset Valley, and see how it runs. Don't change any of the graphics settings other than the resolution, and for good measure, disable the interactive loading screens. (The setting is under the third or fourth Options tab.)
If this doesn't work, try the same except in a new admin user account on your Mac. This shouldn't affect graphics or anything else you've described, but it's worth trying just in case.
Please let me know whether your laptop seems to be getting too hot. it should get warm, and the fans should run, but Sims 3 isn't demanding enough to push the processor to its limits.
@jazzmiint Strange, I can always see my game library even with Origin in offline mode. If it's not working like that for you, that suggests that something else weird is going on with Origin.
Regardless, you should be able to launch Sims 3 directly from its .app in either Applications or Users > your username > Applications. It should work both if Origin is already running and if it isn't: in the latter case, you'd see the Origin sign-in window, but once you input your credentials, the game should load.
I seemed to somehow fix seeing my games in offline mode of Origin, yet when clicking play and opening the Sims 3 Launcher I am met with this message (in the screenshot below) and when I click the play button, it takes me out of the launcher back into the Sims 3 page in my game library where the option to open the launcher is. If that makes sense. I also tried on a different admin user and got the same issue 5 minutes into the game, no change in graphics or any settings (aside from removing the interactive loading screens which I usually have off anyway) and still had the frozen game but the option to click around in the background.
@jazzmiint The error is unsurprising given that the launcher tries to load ads and other data from the internet. But that shouldn't prevent the game from launching at all.
If the game is still working in the new user account, try turning all the graphics settings down to the lowest options. (Change the settings at the Main Menu, then quit to desktop before loading a save.) I don't think you necessarily need to play like that; the point is to see whether you can get things stable and then build from there.
Going by the launcher in your screenshot, it looks like Pets is still active. The pack shouldn't prevent the game from launching either, but it certainly could cause the freezes.
