I can assure you I did Tim, unless Coventry EGBE, Cardiff EGFF and Liverpool EGGP aren't airports!

Nope. I did check that, loaded the .pln and FSX said nope. Its interesting, sometimes it imports and sometimes it doesn't.

Here is the log

Where do I find the logs?

I'm having the same issue with my recent flightplans.

They imported fine just a few days ago and now they won't import at all, to my knowledge I'm not doing anything different to normal so it has me confused.