In the first year in Winter approximately at Day 3-7 after my friend walked into the Event her game Crashed and we are unable to connect on that game file, as we tested a new game file there were no problems to connect. So far the Events posed no problems if either her or me did trigger them so thats something new to add to the Bug list.
Anyone that's having this problem, please feel free to upload the host's save file to the forums here. I haven't fixed this issue myself, yet, but others have been fixing a lot of these, and I'm pretty sure I understand how they're doing it... I'm more than happy to give it a shot. (Unless a more experienced person on the forums steps up before me.)