Hi f-16. You can activate 3rd party scenery from anywhere on your HD providing it's configured properly. The FS2002\ADDON SCENERY folder is a handy place to keep it. My tute will give you the basic idea. http://www.simviation.com/lair/fs2002sc.htm

Don't paste the individual files into the Scenery & Texture folders. Move the separate folders from your FS2002\Scenery folder. There is really no need to move it at all but if you plan on doing so delete your existing 3rd party scenery from the Scenery Library first. Then reactivate it from the new location. I hope this explains it.

The ADDON SCENERY folder is activated by default. This means that any BGL files pasted directly to the ADDON SCENERY\scenery folder will be automatically activated when you next start the sim. This is not the best way to install 3rd party scenery as you will not be able to manage individual scenery areas from the Scenery Library.

If you paste the parent folders into the main ADDON SCENERY folder itself they will need activating via the Scenery Library. This is by far the best method as it makes things so easy to manage. If you already used this method to activate your scenery from the FS2002\Scenery folder it might be better left where it is. As I mentioned earlier, 3rd party scenery can be activated from any location on your HD. The location makes no difference to its performance. The important thing is for you to know where it is.