Hello Manolo and welcome to the forum,
I'm not the most experienced person to help you with Navaids but I'll try and get you started,
not sure about your chart as i cannot see the whole page of this chart, I have the latest charts for JFK and there is no reference for a RNAV approach for 13L only a Vor and ILS approach!
First, if you have the complete chart for JFK you need to add the co-ordinates for ZADUD, WIRCO and JEVNI, which i'm taking them to be Terminal Waypoints,
ASALT and the missed approach DPK are already positioned in FSX
So "ASALT " will be the first "IF" Approach in your list in the ADE Approach list once you have added the type of approach for it,
what i normally do is have a look at how MS does the RNAV approaches, this will give you an idea of how to add this type of approach to your list
Hope this helps you to get started