Thanks, I'll give that a go and see. As a newbie, it would be nice to understand what went wrong and how doing this (hopefully) fixes that, but I guess the aim is to get the system running.
Well, we could trade links to positive and negative postings, and then do a comparison of people's experiences, also positive and negative, with earlier updates, but I don't really see the gain. The impression I formed after reading posts for much of the day on 6.1.1 was positive for bare metal installs and negative for virtualised ones. You have your views based on what you read, I have mine, and the situation is what it is. It has been complained about elsewhere that the nature of this forum is that a huge amount of knowledge on a lot of very complex detail is spread across many, many posts, and builds on history and context going back months and years - plus solutions evolve over time. It is ultimately very hard for a casual and inexperienced user to assimilate all this accurately, particularly while under the pressure of a non-functioning system.
Anyway, I appreciate the help and will report back.