Oh so many posts and so much advice. Thank you all.
I can only speak for my dog and I truly feel that any kind of punishment training would be counter productive for her. I want her to relax and calm down, not add to her worries. I have not heard of Cesar Milan - will google, but will bear in mind criticisms.
She is an extremely anxious 1 year old Saluki / Collie cross with a very unsettled background. Everything about her is nervy. She is all elbows and desperate to please and unpredictable and unsure and mostly can't do right for doing wrong.
We live in a country where her options are us or nothing. No rescue places, government culling schemes, little vet support, no training support.
It's not ideal for anyone, but looking at her now curled happily exhausted on her bed with her toys she is definitely better off with us than not.
Re the barking. Well, I posted at the end of my tether on a particularly bad day, and I thank you all for the sympathy and support and advice. I have started reading about clicker training. I have also found that telling her a firm, quiet "Enough!" and walking away is effective - though not all the time of course. Either she has been better since I posted or I have not been on my last nerve quite so much.
I love the idea of a DAP collar and will try and get hold of one next time someone flies out to us.
I am also going to work an extra walk a day into her routine. She enjoys her walks and is beautifully behaved on the lead.
As for the other behaviours... well. One thing at a time. I simply cannot be on her case for every little thing. It would make her life and mine miserable. I tend towards prevention at the moment. It's just easier.
Oh, she has a crate in a quiet spot which she happily sleeps in, but she never ever goes in there voluntarily during the day. I used to out her in it when we had visiting children, but she started barking when in there. She likes to be with the people.
The next thing I need to work on is her inexplicable recent pooing and weeing habits. She has pretty much constant access to the garden and has been praised for weeing and pooing in it, yet she will hold off going for HOURS and go to extraordinarily sneaky lengths to wee and poo in the children's bedroom. Obviously I keep the door closed, and have put a baby gate on the stairs - she shouldn't ever be in there in theory. I can't tell you how often I stand looking at ANOTHER puddle (or sometimes a squeezed out couple of drips) or a pile of poo scratching my head and wondering if she squeezed through the keyhole to do it. It's like she is on constant alert to seize any opportunity to wee or poo in there. She does it elsewhere in the house too (3 carpets currently at dry-cleaners). But this mission in the kids room is something else. Baffling to me. She is very anxious about her toilet habits. I think she was shouted at for weeing in the wrong place with a previous family. So I never see her do it, and obv never tell her off for it. Just praise the good and ignore the bad. Any ideas about this one?