Now just had my car's 1st service at Perkins. All extremely proficiently carried out and all queries/niggles explained:
Updated software to latest R63. This has added the LKA swipe-down menu. He also said he had reduced the LKA sensitivity as low as it would go - and was sorry, but he couldn't turn it off (as, regrettably, we all know). At least the swipe menu helps, but I have yet to be brave enough to try it when left on. I will do so one day on an empty, wide, open road! R63 has also sorted out the HVAC issues (certainly seems more accurate/responsive so far).
Re the bizarre TPMS readings and 'fake' warnings issue, he said that this problem occurs when tyre pressures are set too low (I had checked all mine at 250 kpa immediately before the service). He further added that they advise for all Trophy and X-Power cars with the 18"+ wheel sizes to pump them up to 3 bar (300 kpa) or 43.5 psi all round. They did so to mine, however there is still a small issue with this in that although the car now shows 300 kpa on the screen, I have since checked the tyres to see if my pump now agreed with the screen - and it didn't - and neither did the pump supplied in the car's tyre repair kit, nor two manual gauges that I also tried ... all agreeing the reading of 285 kpa / 41.5 bar. Either way, at least the TPMS hasn't so far faltered since, as the pressures stand, so I will leave well alone and just monitor it. The other more important factor from all this is that the service report showed that all the tyres were also 0.5 mm more worn (after only 4,500 miles) along both edges - most likely due to underinflation - so hopefully that should also at least get no worse now.
Re the recently noticed very sharp braking at low speeds he put down to the same as the continually noisy brake disks, and made the very sensible comment that the brakes were very little worn and I evidently used the KERS a lot (correct) so he advised every so often turning regen down low and using the brakes HARD for a while to clean them up a bit, which should improve both issues.
Finally, they checked the rear sub-frame lower guard as I noticed it is beginning to show signs of the typical warping, and they agreed and would order in the support bar fix and repair under warranty.
All-in-all, a remarkably pleasant experience; the only downsides being the ZS petrol courtesy car, and unfortunately (tongue in cheek), no bright ideas about improving the iSmart app as being well beyond their remit!