Well, my first thought would be to add the station manually as you would any other object and then make it disappear. When the required conditions are met, it appears via the mission script.
If that's not possible (due to the amount of objects before that point), you could try building the station in the mission editor and then recording all the positional/orientational data; you could then use the CreateShip(); command to add the core and modules to the scene.
Just a thought, does the AddLocation(); command work from within a mission script or only outside the mission rules?
