first of let me say that you are providing a great service, including the one "free of charge", to passionate Flyers like I'm! From your website I've downloaded some airplanes, couple of those very well developed like the Boeing 777-200ER Ultimate pack, practically I'm almost using this airplane in my FSX gold edition with acceleration pack.
I'd like to underline that some Airport's Scenery that I've downloaded doesn't work properly, I've experimented it particularly with two Airports, very nice designed by the way: Klagenfurt Airport (Austria) and Richmond International (VA) USA, both have problems with ILS landing system, the first one impact the airplane against something invisible 30 feet above runway 28; the second one (Richmond) on ILS 02 make the airplane heading the end of the runway instead of the beginning of runway 02.
In both cases I've uninstalled those new Scenery and both ILS works perfectly.
You might have some solution for this that I do not know.
Klagenfurt by Manfred Marbler always crashes the airplane on or near the ground, when crash detection is enabled. I got a confirmation about this issue from the designer, there is a bug from converting the scenery to FSX.
Just disable crash detection in the FSX settings and it should run.