I've got one and used it once during Dukan. I was trying to make yog ice cream. If you eat it as soon as its been in the maker it would be smooth and soft to eat, but putting it in the freezer for future use didn't quite work, it was too solid.
I googled recipes for low sugar, then just adapt for Dukan....as in no fruit. I think I used a full tub of yogurt and flavourings and sweeteners.