Make sure all files are there, and also make sure they restarted the game.
Also, they did look in Cape everywhere, right? If the portals go way off the edge for them and the map is some where around Z in the alphabet, then they probably won't see it at all unless they delete some maps.
The map box called "Has Portal" on the front should be checked too if it isn't.
Just some suggestions I guess.
Note to Lilly: I'd most likely help if you made a new thread or other people might answer truly. ^^' I have to go in a sec.