Is the relevant map selected in Homeport? Is detail set to highest? If so check the option settings to ensure all map features are selected.
Yes, the map should display in the maps drop down list. Be aware the first time you use the card Homeport needs to index the map, this can take a while and until that happens the map won't display. You should see a moving green bar under the map, which should show under your 'device', in this case the card. If it's not showing there then Homeport cannot use it.