No rgntool!
You may simply rename this rgn to anyname.zip and then unpack (copy) folder Tracker into root of Nuvi! As result see pictures above.

I doing so! One exception is opening TrackerTOUandPrivacyAgreement_200.rgn file in HEX and deleting first 60 byte (Garmin signature) for the purity of the experiment I also unpack (copy) folder Tracker to laptop and then simply synchronize content of laptop and device when it is necessary.
P.S. This method have one disadvantage the version of current update not changed in GarminDevice.xml and so WebUpdater sees previous version It is not problem for me I remember in the face of all of its soldiers

The technical rules of Garmin call to follow, but I not doing so See below:

The first version is online installation from Garmin with WebUpdater.exe:
Code:
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The second version is offline installation with WebUpdater.exe (it may be not work sometimes!?):

Code:
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