arr.. Then it's somewhat odd, not sure I had this issue myself.
You do have just 1 version of the map in the map maker yar?
Unless there has been any secret update to the game, you shouldn't need to export the map at all since the exports works the same as the map itself. I'd say clearing the export folder from your map unless it's something you already tried.
Go into cape and see if your map portal still is there, if there's no portal something is wrong, if it's there, it's in order and try going into it again.
If there's still no result of the new map being there, go back to the map maker and uncheck the "has portal" box in the world tab.
The portal in cape should disappear. If it does, Add a random object to the map, and check the "has portal" again and make sure you save the changes and try again.
If the portal would still be there, I'd say something is really wrong cause you don't have any exported map, and you don't have the one in the map maker using a portal.
Play around a lil, I'm not actually sure what's causing this unless you actually have an old copy of the map laying around.