Unable to browse folder for some top level Tags

[n00bs945]

Hi Simon

As a very new user of MinimServer, let me first thank you for the great work done!

I'm having a strange behaviour while browsing directories...
= at the top tree, for Orchestra and CHOIRCONDUCTOR indexTag only,
> navigating using ONKYO is blocked (red crossed folter idem)
> navigating using foobar is allowed

Navigation within other tags works just fine

My config:
> MinimServer-0.8-update-65 installed on a Synology server
-server-
.indexTag: Genre, Album, All Artists:Artiste, AlbumArtist:Artiste de l'album, INVOLVEDPEOPLE:Artistes cités, Band:Groupe musical, Composer:Compositeur, Conductor:Chef d'orchestre, Orchestra:Orchestre, CHOIRCONDUCTOR:Chef de choeur, Date
.mergeFolderAlbums: false
.tagOptions: Album.sortTags={Album, Artist}
- Advanced -
.tagCustom: AlbumArtist.displayRole={artist}, Composer.displayRole={artist}, INVOLVEDPEOPLE.display.multiTag
.tagFormat: Artist.displayFormat={$artist$orchestra$conductor}, Title.displayFormat={$title^$date^ [^]}

Any advice would be welcome

(already tried rescan, reinstall...)