Hello Matt,
Thanks for jumping in and offering a suggestion. In the meantime I looked at some correspondence I had with PG tech support people (God bless 'em) years ago on account of a vague memory of something like this happening ages ago, and it turns out the advice I got then, ie make sure your "Asio always on" checkbox is ticked, is exactly what I needed to do.
Not sure about the rendering problem yet, I haven't checked that, but the other items in my list are resolved.
And yes I did have to install everything again, or should I say my fastidious and thoroughly computer-literate friend did. Every computer user who can't quite do for themselves should have a Richard in their life, and I'm one of the lucky ones.
Thanks again,
Clinton.