Amaya 9.99-2 WinXP dt and dd buttons

Hi,

Amaya 9.99-2 WinXP has two buttons in the tool panel related to dt and 
dd elements, but I can not figure how to use them.

I would say that a dt element should be transformed into a dd element 
when the user clicks the dd button, but it does not work that way.

Is the behaviour of these buttons explained somewhere?

Best regards,
Bartolomé Sintes (http://www.mclibre.org)