For full details about works please see How do Works work?
In the context of Melco and MinimServer works are designed for the usual Classical music case.
If using MinimServer SongKong Classical profile when browsing your music by work MinimServer will use the value of Overall Work (except for multiple level works such as Operas this should always be same value as Work field). If the Overall Work field is empty but Work is not empty then MinimServer will use Work instead, but this situation should not usually occur.
So here when you are browsing by work using the SongKong Classical profile you are browsing by the value of the Overall Work
The other standard profiles provided (Pop/Rock, Jazz, Default) do not make use of works.
When you are playing a work or album songs are grouped into works based on the value of MinimServer Group field. Movement and Movement No fields are not used by MinimServer, MinimServer uses the Title field for the movement name and the movement number is worked out by combining Track order and the MinimServer Group field
By default on a Melco SongKong shortens the Title field for Classical albums to remove any work information. This is the Shorten Song Title to the Movement option on the Classical tab
and should usually be set to Yes if using MinimServer (because it doesn’t use the Movement field).
So here when you are actually playing an album the tracks are grouped by the MinimServer Group field (not the Overall Work field)
If you select a work you can see the tracks with it, MinimServer is displaying the Title field (not the Movement field)