The key finding, which is relevant for this issue:
The db_name attribute entry must be the ROM's corresponding Exact Game Platform Playlists Name.lpl (e.g. Nintendo - Game Boy.lpl) in order to be associated with the correct metadata and thumbnails.
Here is a screenshot which shows that db_name gets set to Name of the new playlist.lpl which will result in thumbnails and metadata not being found in your custom created playlist:
The web app as hosted as of 2022-02-14 transforms
db_name
to that of the playlist name.That is wrong. But no wonder, because the user documentation on this was wrong!
The key finding, which is relevant for this issue:
Here is a screenshot which shows that
db_name
gets set toName of the new playlist.lpl
which will result in thumbnails and metadata not being found in your custom created playlist: