Hello again,
I found myself a solution:
re below 1. GSX seems to recognize for exclusion only those default Jetways (CTRL+J) that are in the AFCAD. All others, not in the AFCAD, are not recognized by GSX as they seem to be static ones and part of the scenery, even if looking identical to the default ones. Example: (FSDT-) PHNL Gate 7 Jetway 1 = in AFCAD, Jetway 2 = not in AFCAD.
re below 2. fixed by Update November 28, 2019
re below 3. considering above Jetway2 static which must be excluded, if possible, by renaming the corresponding scenery file, GSX does not know where exactly to position the replacement SODE-Jetway and puts it somewhere in the gate area and the user has to reposition and align it to the bridge using the NumPad.
After each Live Update the corresponding scenery files have to be renamed again because originals are replaced in the update.
Not sure if my conclusions are correct but they works for me - Umberto, can you pleased comment on this?
Peter