Should have thought about it sooner: the solution is to instantiate a new gallery object which root is the highest level album containing my photos, then call the `printAlbumMenuListAlbum` for this sub-gallery.
Here it is:
`
$myPhotos = new Album($_zp_gallery, 'galerie/');
$albums = $myPhotos->getAlbums();
printAlbumMenuListAlbum($albums, $albumpath, $currentfolder, $option, $showcount, $showsubs, $css_class, $css_class_topactive, $css_class_active,$firstimagelink,$keeptopactive,$limit);
`