The zone view is important if you want use teleporter shrines. If you toggle it on you see a pallet of your zones. It useful to toggle the zone view on if you want to add a lvl file to a zone. The pallet consists of the zones you created in the Art Manager and included in your teleportmap.dbr file and the name layers you created in the Editing mode. Also all your lvl files are colored in the zone color they depend to.