The fuel pressure regulator is the one the vehicle came with as far as I know. When it first broke down one of the AA men pulled the input hose off the FPR and fuel comes out of it with the ignition on. I've tried it since and there's still fuel coming out of there. I've not done any further dismantling of the FPR or fuel pump yet.
If it turns out that there is a signal at the injectors, I shall try my spare fuel pump and see if that makes a difference, and if not try the FPR.
Oh, the last time it fired was around 4 pm on the 19th of December. Aside from the AA man's aerosol, the engine has been completely silent since. From what I read on here, these engines will run if there are things wrong with them, just not very well. Timing out, the odd injector failure, gaskets leaking, hairline cracks in the cylinder head, poor fuel feed, injectors not coded to the ECU and so on, they'll at least cough a bit and turn over under their own steam, they just don't sound very nice. Something's happened that's just cut it off in its prime.
On the positive side I've done a good few useful jobs on the Land Rover over the last few days. New fuel filter head, a service, new injector washers and seals. I even changed the wiper switch while I had the dash apart this afternoon.