Need Help on a Trigger

I'm working on a time-based trigger. It looks like this:

Event - Unit Enters A Region
Condition - Unit Belongs To A Unit Group
Actions:
- Order Unit (Entering Unit) To Move To Region A
- Wait (Until Unit is in Region A)
- Wait (Random number of seconds, from 15 to 32)
- Order Unit (Entering Unit) To Move To Region B
- Wait (Until Unit is in Region B)
- Wait (Random number of seconds, from 15 to 32)
- Order Unit (Entering Unit) To Move To Region C
- Wait (Until Unit is in Region C)
- Wait (Random number of seconds, from 15 to 32)
- Order Unit (Entering Unit) To Move To Region D
...
etc.

This Trigger creates a patrol path, forcing a unit to move from one region to another, in turn, and wait 15-32 seconds there, then move to another region etc. This works perfectly for 1 unit. But I want to throw in some more Patrolling units. For more units, trigger data overlap because when another unit triggers this trigger by entering a region, the one that was in before stops, as it is no longer Entering Unit. How can I solve this problem?

You need to break this up into many smaller trigger.

Have one trigger for each enter region event. While this makes a lot more triggers it allows you to do more things. For example you cant set up random paths by having it so when a unit enters the region it picks a random region or from 2 regions and sends him to one of them. Just remember to use conditions so that it only effects the units you want to have patroling instead of every unit.