when showing pictures fully displayed, it would be nice to load next without changing view mode (maybe by tapping left or right part of display or by using cursor)!
to be more consistent to your wonderful design you have to transfer your new "floating" tapping effect to icons on the sidebar as well (ie floating between browser and player-button)!?
upnp servers are only discovered when taking a look into the first folder-icon, better Mediabox discovers automatically in the beginning
playlists are empty when starting Mediabox again (maybe only concerned to server-linked playlists?!)