uhhhh if im not mistaken i think there is a spell in the "spells" section on this sit that lets you toggle between auto aquire and between "only when you order-aquire" if this helps please tell.
Yeah, it's called "hold position." You don't need triggers for that, unless you order non-player controlled units to do that under the "Units- issue order without target" trigger. Or you can simply pause the units and unpause them when a specific event happens, also. -VGsatomi