phenocom,
to finally reply to your question, yes you have all the files in the correct place.
I'm basing my reply with the information you have given: if you see both Addon Manager and Couatl menus under the "Addons" menu, and you have not mistakenly installed the update instead of the full installer (which, from your file's list, doesn't seem to be the case), there aren't many explanations left:
Check the KFLL scenery has been added to the Scenery Library.
Do you recall having error message during the installation about problems with your scenery.cfg ? If your scenery.cfg already had an error before the installation, the installer would have warned you and didn't touch it, not adding the KFLL area to the Scenery Library
If the KFLL area is added to the Scenery Library, is also active ? Check you haven't disabled it, for any reason.
Also, could you try to install the Stand-alone Addon Manager for FSX, available here:
http://www.virtualisoftware.com/binaries/setup_addonmanagerX.exe