Sims 4 won't let me load my household's

Hi, 

I have recently gotten a Mac and downloaded sims 4 on it, but starting last night I can't play the game really. I can create households and save them, but once I try to place them in a lot or play an old save file it can't load my lots or households. It loads for a while and then just takes me back to the world selection screen. 

I've tried going to the support page, but I keep getting a 500 error saying they are having internal issues. While I assume that explains why my saves won't load anymore I haven't seen anyone else having this issue and want to make sure I don't need to delete my saves.

While I do have some mods added I've had no issues with them, and even deleted some more recent ones incase they have bugged my game. If this could still be an issue caused by my mods does anyone have tips as how to check to see which one is causing it?