With OSM selected, the openstreetmap background ( http://www.openstreetmap.org ) is displayed on the map with the "real game lands" cover overlayed with transparency above.
Adjust the land color (or gray) in the profile as well to get the desired display.
Watch out ! Running aground is trigered on the "real game lands", not on the OSM lands. It can be confusing when they don't match exactly at high zoom level.
The basemap layers "watercolor" and "terrain" have been added as well.