I have modeled two parking lots as zone connectors at different locations and assigned both to the same zone. If the relative flow (rel. flow) for both parking lots is 1.0, how does PTV Vissim divide the traffic originating from this zone? If there are 100 vehicles originating from this zone, will each parking lot get 100 vehicles, or does it split the volume in half?

The traffic volume originating from this zone will be split evenly (on average) between the two parking lots.