You should be able to upgrade from anywhere in 6.7 and it doesn't really require a fully functioning board since I believe it just reads the configuration files in place and does the importer; so I'd take and install v7 to the area that you import (just before you create an admin user I believe) and then run the importer and check on it. I'm sure it should run fun (so long as the classic install exists currently).

My only idea as to why the classic upgrade could be nerfed is if you overwrote one of the vars_ files.

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