Yes, it was PI. Great place to fly from. Nearly as good as Emma Field.
I found the (an?) answer to my recent crash problems. It was obvious that some FSX add in somewhere was causing aggro - but which one?
Simple - kill 'em all!
Go to the fsx.cfg and delete all the lines in the [Trusted] section.
Don't panic. You'll only have a few to activate first start. Over the coming days you will have to re-grant permission as you fly more and more planes in your hangar, but that is no major problem. If you occasionally try the plane (in my case the Cera 412) then if it crashes again, you can narrow the culprit down.
In my case I reckon it's too many beta tests. Most models are installed manually and inevitably I probably loaded one or two wrong - or didn't unload the old when I installed the RC.
The only bug now is saving a flight in flight. What a surprise that was...