Is it possible to set up a JRiver expression that shows a certain field only for a given genre? For example, when viewing "Classical" genre, it shows [Conductor] field in the panes, but when you switch to "Rock" genre, the [Conductor] field goes away. Another great feature would be to show all fields that are not null for a given selection of genre, album, artist, etc.
This would be awesome for those of us with a very diverse music collection, since not all fields are relevant to all genres.