Originally Posted by dlh62c
There's no need to remove the SD card.
Think of the Montana like a removable usb drive and the installed SD card as another. Transfer anything you want to either by dragging and dropping files. Any maps you want the Montana to see are stored in the 'Garmin' directory with a *.img file extension. Any files containing waypoints, tracks and routes you want the Montana to see are placed in the 'Garmin/GPX' directory with a *.gpx file extension.
Using Basecamp you can create a new 'List' that contains all the waypoints, tracks and routes for a single trip you might be planning. You might name the list 'RideUtah'. After your done planning in BC, right click on that list and a window will open. Select 'Export', you can export (save) the list contents to a location of your choosing. Place it in the 'Garmin SD (?:) Garmin/GPX' directory on the microSD card in the gps. The file will take the name of the list with a *.gpx file extension (i.e.RideUtah.gpx). The file is a neat grouping of a set of related items. Upon bootup the Montana will load the file.
To help cut clutter, you might create a new folder on the SD card called 'My GPS Rides/Utah' and drag and drop the 'RideUtah.gpx' file there when you no longer wish to see or use it. I created and use a directory called 'My OSM Maps' to store various country maps, *.img files, that I'm not using. I don't need the gps or BC to load a map of Peru if I'm riding in Missouri.
I hope that made sense.
One can certainly do GPX file drag&drop into the Montana's/µSDCard storage. BUT, if you do that you will negate the optimization that BaseCamp will do with your data when it transfers it to the Montana. If you just do drag&drop of GPX files you will also create duplicates in the Waypoint Manager of any Waypoints that you have used in Routes.
I recommend using BaseCamp to do data transfer to the Montana and allow the system to works as designed. Map's on the other hand, once in IMG format, can be copied to the Montana or µSD card without issue as long as you have any necessary unlock codes also copied.
All of these questions and more have been discussed in the Montana thread