Hi Phil,
I anticipate that there will be people better qualified than me coming along very soon, but in the meantime, here are a few thoughts.
Having had my share of issues with 14CUX injection relays this year, it transpires that new Bosch relays of the correct type (0986AH0602) are often faulty out of the box....in my case, the car ran OK until it was warm, and then would not restart until everything had cooled down. I replaced my new one with one of the originals, and all was well again.
The other easy thing to check is as many earths as you can find - including the one on the back of the left hand cylinder head. One earth on my car was on the bulkhead immediately below the bonnet hinge, and the bulkhead paint concealed something that looked like it had been under the sea for a couple of years. I'm not sure that cleaning it all up did anything positive, although it made me feel better!
I'm not a million miles away from you, and I do have the RoverGauge software, plus some noid lights, so (after the multiple low loader trips we have made this year) I can at least claim a small amount of knowledge. Good luck with sorting this one out, and do keep us posted.
Dave
