Issue with garmin eTrex20 and map of Georgia

Hi!
I have had a trouble with detailing map of Georgia from http://garmin.gis-lab.info/# .When I look at the map with BaseCamp or MapSource from my PC it’s OK, but on Garmin eTrex20 I can see neither streets of cities or trekking routes. Is it kind of compatibility problems with osm and Garmin?

See https://forum.openstreetmap.org/viewtopic.php?id=62468