... I'm hesitating to install it, [version 6.16.1] not knowing if I should first uninstall version 6.16.3, and would doing so delete my user license, etc.
I have installed older MapSource versions without uninstalling newer ones, although not this particular version, without trouble. These update files are apparently happy finding evidence of any
If you want to be very cautious, you could do a full disk image backup before going back. Or you could copy the entire Garmin folder from the Program Files folder and also set a System Restore point. In case of trouble, restore the program files and let System Restore return the registry to its former state.
The maps themselves are licensed to your GPS receiver, not to the computer or the MapSource product. You may have to connect your GPSR once to let MapSource make that connection.
Anyway, I just reproduced my problem. I tried to open the ACA files of the Northern Tier used with my copy of Mapsource 6.16.3. Both the gpx and mps files produced the pop-up message, "! No error occurred", and the file data does not appear in Mapsource. Previously, I was able to get Mapsource 6.16.2 to open the mps file format, so my upgrade to Mapsource 6.16.3 made things worse. I also verified that Mapsource 6.16.3 does open the gpx files that I obtained from American Discovery Trail.
The problem is that GPX is a very "loose" standard. One can write a great variety of conforming files easily, but it is really hard to program successful reading of every
If my records are correct, I prepared the problematic GPX files with v6.15.11. As I wrote earlier v6.16.1 reads them OK, so you should have a workaround there. If for some reason this "Plan B" does not do it, please PM me to send the proprietary GDB format files to you.
Meanwhile, I will get on to Garmin tech support to see whether they know that their current versions choke on GPX written by their earlier version.
... I'm not that familiar with Basecamp at this point, and I'm curious why Garmin appears to have two competing products.
Of course they do not say, but I suspect Base Camp will eventually replace MapSource. The latter is getting long in the tooth, has a--to be charitable--unconventional user interface, and is increasingly difficult to keep free of defects, as the GPX mess testifies.