Installed 20151026103510_161_osm_maps.zip from the github repo. Got, activated and inserted a new Mapquest API key into ~/oc-content/plugins/osm_maps/index.php. Server root php.ini prerequisites are met by default. I created a listing with Country, Region, City and zip code. No joy. Location map does not appear on the listing page. Anyone else have this problem?
I withdraw the question. Problem was solved on this forum