I was finally able to download the .gpx file from my Garmin Nuvi 2797. The problem was with the micro USB cable. I bought a new one and it works now. I'm lucky it's the cable and not the connector on the Garmin. That makes me happy.
Here's a few screencaps from Google Earth showing my route for my recent trip across the NW corner of Arizona.
This one shows where I turned around on the hard section of Nutter Twists Road.
And here's the Honeymoon Trail down the Hurricane Cliffs.