When I copy a route I've created to the New File folder, I always see extraneous small files have been added there (before I copy anything).
Why is that? Can I just delete these or do they have a purpose?
You can delete them.
I wouldn't delete them unless they are old. Garmin Express is copying files there for things like true up. Those files will get processed when you boot your device.
Restart the unit and see if they go away.
