Thanks to all and especially Jason to propose to help me directly.
But Zap you're a genius. My problem was exactly the one you described. In fact I designed my Pronto and then wanted to attribute the correct actions to all buttons. I just try and the given buttons are now visible.
Again thanks to you two but where in the manual does it say that buttons are greyed until you have an action for it?
Good afternoon (well at least for Europe forumers)
Cheers,

Bruno