I’m aware of an issue where the game may crash when loading into a lobby or when another player joins. This was a bug that appeared occasionally during development, and while it may now be fixed, I’m still keeping a close eye on it.
This is currently my top priority, and I’ll continue working on it if the issue is still happening for some players.
For the time being, the crash usually seems to happen only once per player joining, then stops until the computer is restarted. So, as strange as it sounds, trying again may allow you to get into the lobby successfully.
I’m really sorry for the inconvenience, and thank you for your patience while I work through this.