you just get an normal scenario file set up the cammera view you want ( using the camera track trigger) and fill it with eyecandy and make some events happen.
then just save the scenario as what ever you wan't ie my menu then save another copy as ~aom_pgs_atlantis.scx
then when you go to the menu the menu you made should appear like in the screen shots ( only if graphics are set to high). there are also menu mannegers around so you can have more then one menu. if you want to delete the menu just delete the ~aom_pgs_at... .scx file and you will get the original menu back because it is stored in the scenarios2.bar file snd will not be overriden.
if(1 != 0)
{
cout << "Age of Empires Rules" << endl;
}