Hi everyone!
Please update your game. Whether you are on the default, beta, or alpha branch, ensure your game is updated to the latest version. You can do this by verifying game files. Keep your game updated as I publish more improvement constantly.
After some talking and reading, I can say with decent certainty that the mod spread by uploading itself onto the Steam Workshop by overwriting your own uploads. It also reset your preferences, deleted contraptions, and reset your achievements. It seems to have had no other effects or means of spreading.
I've been publishing patches that prevent this mod (and mods like it) from being loaded. If you are on the latest version of the game, it's safe to open (even with mods).
As for the Workshop, unless Steam responds to me soon, I still can't provide an estimate on when it'll be reopened. However, once a large enough percentage of you have updated the game, I can open the Workshop anyway, but modders will have to manually rollback their uploads. Still, this should be postponed for as long as possible in case Steam is able to mass-rollback the Workshop.
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