Keith .. thanks very much for your answer ... it is what I had expected!
If I am allowed one follow-up question (without further payment!), then i would want to ask you whether the only way of carrying the capital loss forward is by literally waiting until such time as one becomes liable to a further capital gain in a future year, and then use the offset of the value of the loss to reduce the liability in that future year.
That sounds at though it might be possible?
The only problem for me is that I am emigrating to Australia in early 2017 (hence the reasons for selling my assets now) and will not be subject to tax in the UK (unless, I suppose, my pension is still taxed here?). But no likelihood of being subject to capital gains tax again in the UK after I leave the country.
Thank you for your excellent support.
Just one additional point. Australia does not have CGT as such, any capital gains are added to you income and subject to Oz Income Tax.