Cover artwork for parent folder

[gbrist]

I am new to Minimserver using a Synology DS218+.
I am migrating from a Seagate NAS that used Twonky.
I am using the default Minimserver properties (2 x attachments)
Using HiFi Cast on the Tablet ( although same issue with Foobar200 mobile and Mconnect HD )

My folder structure is like:
Artist
Album 1
Album 2
Album 3 etc etc
So far the only thing that is disappointing is that when looking at Folder View there is no cover artwork in the parent folder where as with the Seagate NAS there is and the Parent folder displayed the first album cover listed withing the Parent Folder..
Actual album cover art is fine just the Parent Folder is the issue - and it displays this annoying "tag view" icon ( above the list of albums, first level down from the parent as in attachment 3 )
Same FLAC lossless files on both NAS's. Ripped by dbPoweramp.
I can "force" an album cover to appear by copying a folder.jpg into the parent directory.
ie
No cover art appears in the parent folder icon if:
Led Zeppelin ( Parent folder )
Led Zeppelin I
Led Zeppelin II
Led Zeppelin III
Led Zeppelin IV
But if I copy cover art from one of the albums to the parent directory the parent directory will display that cover art picture
ie
Cover art appears in the parent folder icon if:
Led Zeppelin ( Parent folder )
Led Zeppelin I
Led Zeppelin II
Led Zeppelin III
Led Zeppelin IV
Folder.jpg

As I have many Parent Folders (almost 1000) I would rather think there may be a setting I have missed rather than have to add a Folder.jpg to every Parent Folder.
Hopefully I have explained my situation clearly.
Also would be interested in any whether I should be making any changes to the "default" Minimserver properties to give a better result overall?
Thanks