to be overburdened! The limit is 8 but there were 257 items.
This crash tends to happen when joining a multiplayer game with a lot of content. Try removing mods that introduce lots of recipes or schematics (HUB/MAM/shop unlocks) or Mod Savegame Settings. It can sometimes take a while, ex. a certain number of buildings placed or schematics to be unlocked, for the problem to actually appear. FICSMAS recently added a lot more schematics which can make the problem threshold easier to hit. The SML team is trying to find a long-term fix but it's a very complex issue to solve.