Thanks for the replies everyone! Glad to hear the laws haven't changed. A printed copy of the LHD laws from the RMS site is now in my glove box.
My first impression was that he thought he just needed to say something to me. Maybe because the car is a bit louder than most & attracts a little more attention in a crowded servo.
The car has all the requirements as Dave mentioned like LH & RH mirrors etc, Just wanted to be sure I wasn't doing the wrong thing. I would really hate to have to put a big ugly LHD drive sticker on the back of the car.
There's enough big ugly things in it already.