I didn't actually expect a response here because I am sure there are not dozens of bloggers clowning around with the Alfursan programme. No one in their right mind (whatever that is) would choose Alfursan as their main Skyteam programme.
But I would like to report success with my quest to make an award ticket using somebody else's miles with Alfursan and I want give a few data points as to how I did it. To use somebody else's miles (with their permission, of course) you first have to create an account for yourself. That proved impossible on the Alfursan site because of the IT (probably works fine in Arabic language). So I did it by emailing the service center. They required a copy of passport data page and ID card, if applicable. They initially sent everything in Arabic, and upon request sent the same in English a few hours later. I wasn't sure if what I thought was the membership number read backwards, like the Arabic language (it doesn't).
I then went to my brother in law's account and nominated myself as a family member and it was accepted pending review. Later, having received an email notification, I went to my own, newly created account and confirmed my acceptance as a family member (which meant I gave up my 'rights' to my own account). Then I went back to my brother in law's account and activated my family member status.
I then booked with no difficulty at all at one way itinerary in Business class from Muscat to Frankfurt via Paris, thus avoiding having to overnight in Riyadh. No problem to use my own credit card for the taxes. Actual routing:
MCT-RUH SV Business
RUH-CDG SV Business
CDG-FRA AF(A5) Business
60,000 miles plus USD 115.57 taxes