Great to hear users might not need to edit the path anymore as in the past sometimes it faulted.
Users *never* had to edit any path, even before, when the .BGL was in use.
It was a myth spread by some (wrong) instructions in some profiles whose authors apparently failed to understand the explanation in the manual that, in order to simplify sharing of profiles, the full path was never taken into account, and the only thing that mattered was just the filename of the .BGL, as long it matched the .BGL loaded, the rest of the path didn't count.
in the past, you could place the .ini file in the scenery folder of the scenery. - Can this still be the case or does it specifically have to be placed in %appdata%\Roaming\virtuali\GSX\MSFS?
You suspected it correctly: you can't do that anymore, profiles will only be read from the %appdata%\virtuali\GSX\MSFS folder ( BTW %APPDATA% is a shortcut for \Users\YOURNAME\AppData\Roaming, no need to add Roaming again if use %APPDATA% ), and this is a side effect of the fact GSX doesn't go into the Community anymore to search for files.
The manual explains this, Page 87.