Hi Fabrizio,
Did you find any answer do your question ?
sap note 2292571 - SAP S/4HANA output control - technical setup says that "ADS is part of S/4HANA, hence a license is only needed for interactive forms. Print forms are included in S/4HANA. See SAP Note 750784" ....
and that is pretty much all I could find.
We are running S/hana 1511 FPS02 and there is no trace of ADS on our server, could not find any documentation ...