This is because there is an old OS installed in the Nova. Download the
OS4.1 for the Nova from the Novation website and install this into the
synthesiser. This software will have many other benefits besides
activating the special buttons.
http://www.novationmusic.com/downloads.asp?productid=20&type=1
http://www.novationmusic.com/downloads.asp?productid=20&type=1