When I make multiple maps I tend to use quick menu builder to build my menu and burry my games within it's directory then put it all in an installer but the security that most developers want wont exist in this method... Only reason I go this route is I got a group of friends I play deathmatch games with every other week and they don't build games so no worries on anything being stolen.
-------Edit-------
Wow pulled a search, found nothing then I tried a google search and unless you type it in as "core map" you will not find it. Anyways here is the link that Goodman84 was telling you about
http://forum.thegamecreators.com/?m=forum_view&t=105028&b=21
If you think education cost so much you should see how expensive ignorance can cost you