If your Addon Manager shows up in the menu bar, than it's pointless diagnosing the problem with the files you attached. That would be only necessary if you DIDN'T had the Addon Manager in the menu bar, so the files would be needed to undertand why it didn't run.
If you see the Addon Manager under the Addons menu, than nothing is wrong with the software, and is running normally. However, as was explained in another thread, the KLAS release needed an update of the Addon Manager that make it not compatible with previous sceneries.
Of course, if you install the KLAS Trial, it will also update all your installed sceneries, but if you don't want to install KLAS, if you download and install the Stand-Alone Addon Manager installer, it will update the scenery in the same way, and buildings will reappear.
Of course, the current JFK installer that is online now, has been already updated.