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Oh thank you! That's excellent to hear :) Please let me know if I can provide any other info/scenefiles that could help.

Thanks Warren! Unfortunately that didn't work for me, but I appreciate the suggestion! This is a pretty big workflow killer, so I'm not sure what I'm gonna do here. For now I may just have to keep an older instance of unity open to iterate fast on materials, and then copy those into the newer project :( Or abandon this plugin altogether, which would make me sad since I've really liked what I've seen so far!