Well, it finally happened. One of the mods we use has gone belly up and has been removed from the Steam Workshop entirely. The Stacks mod. Unfortunately, this means that new players couldn't join until it was replaced. It also meant that replacing it would destroy anything that stacks!
I made the only choice I could and replaced it with a new stacks mod today. Of course, that means.... All your stacks are gone. If you have been affected by this, please let me know and I'll do what I can to help you with new materials!
Please accept my apologies for this obviously horrible inconvenience!