I arrived home from my trip yesterday and can report that everything went smoothly. In the end, due to health problems in the weeks leading up to my trip, I didn't get the Arabic transcript put into my passport, but like Gunship said, this was no problem.
The first three sectors were all more or less on time, the fourth was just under 30 minutes late, which still allowed me to get the same train home from Gatwick as I would have done had the flight arrived completely on time.
Airline food is rarely very good in economy, but Afriqiyah's seems to compare quite favourably with most, both in quality and quantity. My only criticism is that a couple of dishes were quite spicy. This was not a problem for me, since I love spicy food, but not everyone does, and a choice was not always offered. I was pleasantly surprised by the in-flight entertainment, which had a modern touch-screen interface, and seemed to be very reliable.
For me the only issue really was Tripoli Airport. The departure lounge is small, and not very comfortable. The toilets are in serious need of modernisation too. I was glad I didn't have to spend long there. The staff there were pleasant and helpful though, so it wasn't all bad.
I would certainly consider flying with Afriqiyah again, especially once the expansion of Tripoli Airport is complete, which I gather will be happening very soon.