The importer scripts are designed to be run from the respected final builds of UBB.Classic6 (6.7.x) and UBB.Threads6 (6.5.x).
The global moderator group permission was added in UBB.threads v7.3, so the upgrade path has always been:
Latest v6 build Imported to -> UBB.threads 7.2 -> Latest v7 (it isn't required to do an incremental update to v7.3 as the upgrade utility should do all of those incremental steps for you, but in the past this was a step).
I would recommend running a dry run before spring things down to do a final migration (to ensure everything goes smoothly).
I would also recommend that you run my UBB.threads System Requirements Test script (here
) to ensure your web host is compatible.