Traffic A.I on Map Spawn.

Does anybody Know how to save/set A.I through the map editor? as of the most recent updates you are now able to select the option to spawn traffic with a map on loading however it does not spawn in police A.I. If you use the Traffic control app or the radial menu this reduces the frames of the game and cause significant stuttering along with defeating the option of the aforementioned new feature. So far I have only been able to save police vehicles onto the map but without any A.I. This is really frustrating as it seems like a very simple thing but have gotten to no avail. If I am to have traffic on a map I would want the full thing.
Thanks in advance.
Matt.