The only way I can think to use it would be to get hold of the relevant version mapcreator and create your own maps. It's not that difficult, download the daily dump,
http://download.geofabrik.de/index.html then use osmconvert64 to cut out the bit you want.
osmconvert64 G:\downloads\nigeria-latest.osm.pbf -o=f:\maps\nigeria.osm
osmconvert64 f:\maps\zambia.osm -b=0,-16.7,28.3,-15.4 -o=f:\maps\zambia5.osm
Note in the second one its longitude followed by latitude. Getting this bit right is hard work but JOSM can give you the lat and long.
The free version works fine for this.