The answer has been made clear, yes you can install more than one map. Just be sure to place the .fhm file into C:\\FeralHeart\\Exports in order for the portal to show in Cape of Distant Worlds.
Be sure to throw the .fho files in there too! They allow you to see objects/meshes in the map! .fhw's and .fhs's also belong in the Exports folder, they allow you to see any custom made Skies or Weathers the map maker has made for the map.
Hope this helps! Locking this as it has been thoroughly explained.