Just read the info on the site. It tells you the whole process. I just used the site today with my Autel Jbox and it works fine. Until you pay the fee, you can not download the FMP software from the site.
Make sure you install the Autel software for the Jbox on your PC before you try and connect the Jbox,car,and FMP on your PC.
There is WAY too much to try and tell you, just read the info on the motorcraftservice website. All the instructions are there.
One little note, turn your firewall off before you start if you have one. You can turn it back on when your done. A firewall WILL block your connection.
Good luck, Kevin