Also, I not sure I follow what you said earlier that FSDT or / and beam did not touch the scenery.cfg
I wasn't entirely clear.
The new installer surely won't touch the scenery.cfg anymore, to install the NEW scenery you are installing now but, if it finds old scenery installed with the old system, it will obviously have remove from there, in order to add them using the add-on.xml system.
But, of course, this part of the installer, the one that removes a scenery from the scenery.cfg, has always been the same as it always were, when it removed the scenery during the uninstall.
Fact you said you couldn't edit the scenery.cfg yourself, seems to indicate that something is wrong, maybe a permission problem, or another application that opened the file, which might have caused the installer to fail to remove the old installations properly.
I don't think I ever said I attempted to manually edit the scenery.cfg. I typically leave that to installers and the add/remove device in system settings. Nonetheless, I think I'm in a good place to be advised how to go about reinstalling
Here's what I have done.
1. Under ADD remove Devices I have removed all FSDT and FB scenery including addon manager(s) and Couatl (Closed and Rebooted Computer)
2. Started up P3DV3.4 and it asked me if I wanted to "enable" these same scenery. This brought to my attention that during the migration, the FSDT installer placed two new files in the Program Data\ Lockheed Martin Folder beginning with the name "add-on". The file(s) contained all the scenery I had purchased under the aforementioned developers.
I chose not to enable and continued with loading of P3dv3. Did a test flight in the F15 and then exited
3. Reboot computer
4. Loaded up P3DV3.4 again and this time I was not prompted to "enable". Continued and flew two sessions successfully. However, whilst in flight I pursued through the Menu bar to ensure all was in order, when I came upon a new "Add on" selection. This revealed the perhaps a xml file still exist within my associated files with the pertinent information to enable the FSDT and FB scenery.
So From this point I ask, what should my next steps be?
How should I conduct a reinstall of all scenery (FSDT and FB)?
Should I start from the oldest to the newest or does it not matter?
Will the new procedures follow with any of the scenery I install first (KLAS, KORD etc) or do I need to start with KCLT?
I think this is important, because every previous install was a failure. (with an exception to the initial installed which worked the first time, but closing out P3DV3.4 and restarting it is where troubles began)
Also, I noticed there is now a FSDT Live update desktop shortcut - Can you enlighten us as to how this works. Does it require us to launch it (should we) every week or is there an alternate routine schedule for it (Will a notice be posted in the FSDT forum to run the live update?)?