Gents,
Thank you for the continuing contributions.
Pete explained to me what the log message means, why it comes up, what FSUIPC does in that situation and how I can test everything is working.
I have followed his sage advice and everything has checked out and for now, I have also reverted my [Traffic] options in the FSUIPC.ini to default (not on Pete's suggestion - I did that before he replied) and I have not had that message occur again.
Looking at the boundary map, I can see why I probably get what I get, which is fine as it means I don't have a problem to solve with my set up and you don't have a problem to solve with the software. I can contribute to making my area of the world a little closer to how it is actually set up and I will turn my attention to that in due course.
Meanwhile I will fly a bit more in accordance with boundary map and get a better feel for things now that I am not trying to solve a possible computer issue or conflict.
Kind regards,
Mark