Thanks for the reply.
I have gone through the high command training - did that just the other night. It is maybe a little late actually as this is my second time playing the campaign (which is a little more bug-free than the first time I did it) :)
However the training doesn't tell you how to attach other men to the groups you control (#2 above), or how the scroll-wheel-menu works (#3 above)...
At the moment I'm STILL playing 90% on my own, I find that if I send the groups 2, 3, 4 etc. anywhere near a town they get decimated. I find using the command system a pain to be honest, more trouble than its worth.