Well, thanks for the replies. Unfortunately, everything in your last list of what the migration was to perform worked but the previously existing sceneries that were moved from the FSDT and Flightbeam subfolders and in FSX still do not display the terminals (same as before described in original post). The O'Hare scenery installed with the new Addon Manager setup EXE (oharex_setup.exe) displays fine.
I have screen prints of 1) PHNL after the install with no terminals displaying, FSX Addon drop down menu with Couatl, GSX and Addon Manager loaded and functioning, 2) Addon Manager control panel screen showing PHNL "Installed and ACTIVE", and 3) the O'Hare scenery loaded in FSX displaying correctly. I do not know how to attach/paste images or a PDF into this message using the "Insert Image" menu for this forum (sorry, first time poster). If it helps resolve, I can send separately in JPG or PDF format if you can provide directions. Also can send you the FSX.exe, EXE.xml and DLL.xml if they would help troubleshoot... I have before and after O'Hare install copies.
Seems at this point of troubleshooting, there should be few other possible causes. If no other suggestions, I wonder if installing O'Hare first then follow with all other sceneries after Addon Manager path is set and locked. Would this option also work correctly with setting the scenery installation path for all Flightbeam sceneries installers? If can't get this resolved soon, I am just going to live with the previously installed FSDT sceneries, trash the newly purchased O'Hare and live without any FSDTs that I do not currently own. Love your sceneries and Flightbeam so much I have pretty much abandoned using freeware sceneries, but this will soon get where no longer worth the effort to install for a game.
Please do not suggest reinstalling Windows as I have seen for some other posts. This is the only game on a system primarily used for business. Not an option to reinstall and reconfigure other software to make scenery work.
UPDATE: While browsing & trying to resolve issue myself tonight, have found that all Flightbeam sceneries do work/display correctly after the migration of existing sceneries. The only sceneries that do not work are the migrated FSDT sceneries. Have checked all of them and none display including terminals, nor airport ground/runway elements. Only the MegaScenery photoreal scenery displays (FSDT sceneries are at highest level in the Scenery.CFG). Secondly, was going to attempt reinstalling KHOU for grins to see if it would display after reinstalling, but it wanted to install in the FSX\Fsdreamteam directory not the Addon Manager\Fsdreamteam subdirectory. Also noticed that there is not a airport subdirectory for the migrated FSDT airports containing a __init__.pye in Addon Manager\couatl (i.e. <path>\Addon Manager\couatl\<airport subdirectory>). There is one for common, GSX, Liveupdate, wx, OhareX and each of the Flightbeam sceneries. Is this correct, or should there be subdirectories for the migrated FSDT sceneries?