You didn't give enough info in your post to give a good answer. Here's how I use the type of trigger I think you're talking about.
EAST
PRESENT
condition
(("man" counttype thislist) == 0)
onactivation
whatever=true
You can use man,tank,air,land and maybe there's more ? Anyways, if you want a waypoint activated by it, sync it together, make the trigger of type switch, and it will lock the next waypoint until the trigger condition is met.