I have added patrols for a bunch of my missions and I am now in the process of removing them. They only fire-off haphazardly, they don't start moving until the player is within a certain range, they cause mobs to vanish under the floor on a lot of ground maps, etc.
One of the missions I played for the challenge, has patrols in a hallway. Very buggy behavior.... the guys walk down the hallway and disappear occasionally then reappear.... actually... I think they may have been going into the ceiling somehow.
You need to make sure you're setting the patrol point Y value relative to zero, as the other options don't work (it is set relative to zero anyway).
My observation is that the patrols seem to "start" when the map loads, but they don't actually appear until you get close to the group's spawn location. Which means they'll appear halfway through their route. I can't say for certain that's what's happening, but it seems like it. I haven't actually used any ground patrols for actual combat, so I can't comment on that.
They are utterly inconsistant, I had 3 patroled mobs (set-up the exact same way) all in the same area, doing looped routes in a series of concentric rings. The middle one works about half the time. The inner and outter ones worked for a short time then stopped working.
So, has anyone had patrols actually work, or is it basically unanimous that they're broken? I seem to have had some success using them on space maps, but I haven't checked them out that thoroughly to make sure they're working 100%.