Quote: " But this is an uncomfortable workaround."
Floor zones aren't a workaround, they're how you are supposed to use AI on top of other entities, ie on floor pieces in rooms etc. It's similar to a nav-mesh in a less detailed style.
As to "staying in the zone", you know you can add as many nodes to a zone as you like right? Just shift+click any of the nodes and it will split it into two, you can have a zone any shape and size you want.
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