Permissions for uploading tracks, downloading GPX files and commenting are controlled in this panel. Permissions are set per user group. The Create, Edit, Delete permissions in J!Trackgallery control the creating, editing and deletion of GPX files and tracks. These permissions should only be given to authenticated users (i.e. users who are logged in to the website).
To give download permissions to users who are not logged in, give download permissions to ‘Public’, as shown below.