how do i make 2 floors for cata?

ive seen some pservers with 2 or more floors for catamaze, can anyone tell me how this is done.

you will need to add an npc to teleport your players and then copy out all the generators and changer their settings ... i suggest you do this in excel and then edit the map data and add the map to ini/gamemap.ini in your client and the gamemap.ini in your server