@ You can fill up areas outside the dungeon by using multiple dungeons (Video below)
http://imgur.com/r0mPWmsm.jpg http://imgur.com/FcGFQCvm.jpg
http://imgur.com/NJ5rWtjm.jpg http://imgur.com/TESEo9um.jpg
http://imgur.com/44jbMGcm.jpg http://imgur.com/FrQomukm.jpg
http://imgur.com/idbZGIam.jpg http://imgur.com/poFXglbm.jpg
http://imgur.com/QMZ03dbm.jpg http://imgur.com/WgNmvosm.jpg
The following video shows examples of using multiple dungeons with the same level and the use of Transformation Logic to fill up the empty space around the dungeon
watch?v=RMrhF2xICQc