If you run the installer again and pick the option to add/remove scenery and proceed to the map portion, are the boxes you expect colored in? If not, the scenery did not get installed.
Are you possibly running in demo mode? The Demo only has scenery at KSEA. You should be warned a couple times if you are in demo mode though.
For more troubleshooting, please provide a copy of your log.txt from the main X-Plane folder and more information.