Crashing randomly on MAC

saultrixter​  You say the crashes are random, but is there any pattern to them at all, for example do they only happen in a certain world on a certain lot or when sims are doing a specific tasks?

Please also list the full specs of this computer: everyting under About This Mac including the OS and except for the serial number.  I would like to know whether iCloud Drive is syncing Documents as well.  Open System Settings > Apple ID > iCloud, and if the box next to iCloud Drive is checked, click Options and see whether Desktop & Documents is checked too.