OK got it working - phew!
Basic problem was that I had downloaded a set of firmware - but it was wrong! The one I had downloaded was 16k in size, the one I have now is 7k in size. I got it via https://www.linuxtv.org/wiki/index.php/ ... er_support
and it was located at https://github.com/OpenELEC/dvb-firmwar ... -b40-01.fw
I actually created a new image on a different card and re-configured the whole thing from scratch.
Only other "gotcha" I had was using the correct user id and pwd in the correct place - it has you create an admin id and a user id. That is OK, but when I log in via a browser (part of the configuration has to be done in a browser) it retains the original (default) uid & pwd.
So now I only need to learn to drive OSMC from my keyboard and mouse (I don't have a remote - yet!).