I have been having trouble importing Adif log files into GridTracker.  Talking to other users on Thursday night it seems that others have had the same problem.  I think I have now solved the mystery.

On the Logging tab in Settings it is necessary to identify the files you want to include.  These are identified to GridTracker by activating the “Local file(s)” section (Click on “Menu” and  “Startup”).  The “Add file” button will let you select the path and filename of the file(s) that you want included.  The files will show on the map the next time that GridTracker is started.

In order to see all of the squares you have worked, it is necessary for the Map 
View Filters to be set as wide as possible.  That is with “Mixed” selected in the top 3 boxes and “Logbook and Live” selected in the bottom box.  If you leave “Auto” in the band box, you will only see squares from the band you are currently working.

This video is possibly the definitive guide to GridTracker.  In it, Josh Nas KI6NAZ is guided through the setup and features of GridTracker by Tag N0TTL who is the author of the software.  Be warned. however, it is 95 minutes long and you will need to take notes!!

https://www.youtube.com/live/B4mGq7le3co?feature=share