Well, according to the DBA installation guide you select the “Change feature key label” command (in the Options List) and then use the dial pad keys to change the programmable key labels.
Regards,
Harry
"The legitimate powers of government extend to such acts only as are injurious to others. But it does me no injury for my neighbour to say there are twenty gods, or no god. It neither picks my pocket nor breaks my leg." --Thomas Jefferson