Thanks for the tip. I have sent a message to RRHSG - but it looks like he hasn't been online since Jan. If I had the time I could always pop by his place for a glass of vino- but that will have to wait a bit.

I stepped out to the Rover last night to see if I might have a bit of luck with unlocking and VOILA! All doors opened with the first turn of the key! I know that this was just a fluke event, but at least I got to move it out of the parking area. It was quite surreal sitting behind the wheel since I have only been able to drive it a handful of times. Still need to get a nanocom over here to keep the bad things from happening again. Too many home improvement projects in action to blow the extra money on a nanocom just yet. I will keep you all informed.

I can't remember that far back in the history of your car, Marty will know more, but it certainly sounds like the drivers door latch has got intermittent microswitches. A new door latch may well be the answer - to that bit at least.
Marty sells them so wait for him to drop by...

You may find that the problem was simply where you had parked it. I am aware that the Marie will often have the transmitter for the local flic on it in many smaller French towns, so it could be that the receiver was simply being swamped. If that is the case, as long as you don't park there again (or if you do, only lock it with the key and not the remote), you should be able to enter the EKA and sync the key. Your problem looks remarkably similar to this one https://rangerovers.pub/topic/417-engine-disabled and all he had to do was push it down the road a bit (all, well yes, I wouldn't fancy pushing mine too far.....).

RRHSG should get an email telling him he's got a PM on here, maybe he's just busy now the place is starting to fill up with tourists.