It would never work, because it needs the Addon Manager for FSX to enable it, and not just for the activation, but also make part of the scenery to appear.
We would like doing a proper KLAX (and an EHAM too) for FSX but, what have stopped us so far, is the fact that roughly 40-50% of the users are still on FS9 and, releasing it for FSX only, would mean we would have potential sales cut in half, because there's not much more we could do for it in FS9 and, even if we could, we are not supposed to compete with Cloud9 with the same product on the same sim, not as long they still pay us for the use of our sales system, which they do.