Thanks Nick.
I found that post after I'd made my request and I've now got it all working. It took me some working out but I got there. As you said, an excellent topic and solution to my problem. Thanks for pointing it out to me.
I have noticed one bug tonight though. I did a short flight from Liverpool (EGGP) to Hawarden (EGNR), my local airports. No problem. I then switched to Moorabbin (YMMB) and FSX locked up whilst loading the scenery files and shut itself down. On restart everything loaded up at Moorabbin and I flew a circuit there.
Intrigued, I then switched to Chicago O'Hare and, once again, the scenery didn't load, FSX shut down then everything was OK on the restart. Is this a known bug? I'm using Windows 8.1 btw.