I've received an answer re: BBC1 HD. On the 8130 model receiver you have to go to the MENU and then scroll down to TRANSPONDER LIST. Scroll down a bit further to the frequency marked 10847 (it's near the bottom of the first page) and then press the RED button to SCAN.
My box came up and said that there were 3 TV channels and 0 radio channels and offered the option to add them. Once it was done BBC1 HD appeared at the bottom of the channel list (press CH- when on BBC 1 to get to it easily).
Job done. By and large I've got the box working in the main with a few channel oddities to sort out and a large number of lessons learned along the way. Thanks for your help and advice people!
Interesting that nobody else has mentioned having the 8130 receiver. Don't know whether that means I got lucky or unlucky.
Along the way I've had a professional satellite firm turn down the chance of work claiming the Ross systems are "cheap and nasty" and "had nothing but problems with them". An odd way to react to the possibility of earning a few quid. Still, when I decide I need to upgrade I know one place where I won't be going to get my stuff.
John