Hello again Gents,
There is a positive ending to this particular story! ....... After ringing my local ATS (Durham, Langley Park) who didn't have the adaptor, and not getting any call back from Town Centre Citroen (Main Dealer; why would they bother to call me back for a £30 job

), I eventually got another email back from Croxdale (the place in Durham who had an adaptor but it had broke). They told me that they had checked and their Sunderland (Ryhope) branch could do the job. So good on them for getting back to me....... but they didn't get to do the job - here's why:-
Even though it had actually been a few months since I got the new tyres from E-Tyres (longer than I thought), they responded to the stroppy email that I sent them, and agreed that the E-Tyres Durham guy would visit and take another look at the wheel balancing.
The E-Tyres Durham (it's franchised) owner is called Dave Plumb, and he called last night, apologized for the problems, assured me that he did have the adaptor and had balanced the wheels, but that these wheels did sometimes cause problem with balancing, and that he'd come today at 12:00.
He came today and could not have been more pleasant, knowledgeable, helpful and hardworking. He spent over 1 hour mega-carefully balancing and checking the wheels, talking me through everything and was even honest enough to point out that the wheels were a few grams out, and that this may have caused the problem. Anyway after over an hour, he left and asked me to call him immediately if (after test driving the car) the wheel wobble still existed, and that if so, he'd have a colleague come and check the tracking for me.
I test drove the car and as I got to 65 (where the wobble used to start) no wobble! ..... and all the way up to *sensible* motorway speeds: no wobble whatsoever. The ride is smoother than it has ever been.
So, it's important to admit when we're wrong; Dave admitted that he may have mis-balanced the wheels last time, but I also admit that I was completely wrong to suggest he hadn't bothered balancing the wheels the first time, and Dave is a hardworking, conscientious guy who does understand our cars (and these pesky hubless wheels!

), and I'd really recommend him for new tyres.
Done!

David.
(15) Citroen C1 1.0i 12v Feel
(05) Citroen C2 VTS