On Dailygammon, as here, the server presumes that you intend to play the first (left-hand) die first.  However, if you click on a piece that cannot move the number of points shown on the first die (e.g. because the destination point is blocked), then it automatically moves the second die instead.  (Mechanically this is accomplished by inserting a link on the board for the second die when the first die is blocked, rather than inserting no link as is done here.)  This saves a lot of "swap dice" clicks.  Could that be implemented here?