I'm 99% certain it can't be done, the roof functions are in module GM5, I've just had a look and the only options are:
KOMFORTOEFFNUNG_FB - convertible top opens by holding the open button on remote..Or opens all windows & sun roof on non convertible
KOMFORTSCHLIESSUNG_FB - convertible top closes by holding the close button on remote..Or closes all windows &sun roof on non convertible