You can tell if you have a GPS fix by looking at the status bar icon (you may need to add the status bar: settings/panels/status bar and enable minigpds). If the icon is white, gpsd is not running and you'll never get a fix (click the icon and select 'Start GPSD'). If it is red, gpsd is running but hasn't locked on yet. If it is green, you're good to go and enabling gps in maemo mapper should work fine.