Apologies adeace, I didn't respond to your query regarding my software issues.
It was finger trouble at my end!
When the techie looked at my car he realised straight away that I didn't have MG Pilot on the right setting.
The manual explains four different levels of adaptive cruise control and like another post here I had become frustrated with the car slowing me down a long way behind the car I was approaching. My solution was to change the adaptive cruise control to a gentle warning bong only, leaving me in full control of the brakes, but this had the unwanted side effect of completely blocking the cruise control.
The solution that we came up with was to put the adaptive cruise control in the third of the four settings and then juggling the last hand silver button left or right to keep the required distance from the car in front. Pushing to the left comes up with a 1 and a picture of a car, but it is more than one car length, ideal for 20 or 30mph limits. I then toggle it to the right to 2 for 50mph limits and right again to 3 for 70mph driving. This practice seems to keep my car at the right distance. However, it doesn't have the brain to anticipate anything, so if you see brake lights come on four cars ahead it is better to react yourself rather than to wait for the car ahead to slow and then for the HS to stand on its nose.