You can try uninstalling and reinstalling again, and use only the FSDT installer, not a old Cloud9 installer you might have.
If you see the Addon Manager, and the scenery doesn't show, check it has been added on the Scenery Library. If your scenery.cfg already had an error, the installer wouldn't try to add the scenery but, in this case, you should have seen a message at install time about this, and the installation would abort.