there is an allied computer player with campaign area town AI. I have set some of the units of that player to order: move to location. but the unit must go to several locations.

I used move location to follow the unit. That works ok. but the problem is, the unit has to move to several places. So from location A to location B to location C. and as soon as the unit moves at location B, I can't send the unit to location C anymore, because of the move location trigger that follows the unit. Is there a remove location option or anything?

trigger i used:

from location A to location B:

if player moves unit to location A
then issue order to unit at location A move to location B
center location A on unit at anywhere
preserve trigger

from location B to location C:

if player moves unit to location B
then issue order to unit at location B move to location C
center location B on unit at anywhere
preserve trigger

Easiest done with a death counter:
3 locations A (start), B and C mark the waypoints, 1 location 'F' follows the units in question for reorder.
Yellow parts not needed if you don't want to loop the patrol route

C: Death counter 'Patrol' is exactly 0
A: Order units at F to B
preserve

C: Death counter 'Patrol' is exactly 1
A: Order units at F to C
preserve

C: Death counter 'Patrol' i exactly 2
A: Order units at F to A
preserve
(skip this trigger if you don't loop the patrol route)

C: Player brings at least 1 men to A
A: set death counter 'Patrol' to 0
preserve
(skip this trigger if you don't loop the patrol route)

C: Player brings at least 1 men to B
A: set death counter 'Patrol' to 1
preserve (only needed if you loop the patrol route)

C: Player brings at least 1 men to C
A: set death counter 'Patrol' to 2
preserve
(skip this trigger if you don't loop the patrol route)

Why do you need to have the location follow him? Does the AI take control if you don't?

exactly

it seems that ordering an computer player is actually possible, the unit was ordered by another trigger. you even do not need to use 'move location' , just order. there are so many triggers in this map..