Hey Neil:

I finally have the GarminDevice.xml but, the GPX folder is still there. UGH


Map updates available for a fee with with GE.

nuMaps Onetime City Navigator North America NT (A single update to replace your existing map with the most current version)
and
nuMaps North America (Pay once and update your map anytime a new version is available)

I followed your instructions as noted, now Garmin (D) has
Garmin and System Volume Information

In the Garmin folder is:

GarminDevice.xml (MS Edge HTML Document)
in addition to the files I mentioned in my previous post

System Volume has:

IndexerVolumeGuid (File)
WPSetting.dat (DAT File)

Hope this is helping somewhat.

Cheers

Jack