I think I have it all sorted (well nearly). What I was doing wrong was trying to
Skindle non Amazon
Kindle for PC books.
So I have now got the system;
1 -
Buy Amazon book and have it sent to Kindle for PC
2 - go to users folder\my documents\my kindle content and cut book from there and paste into the c:\skindle directory
3 - rename it to something short like book1
4 - run 'skindle -i book1.azw -o bookdone.azw' where bookdone is a name you want to keep and easy to remember
5 - cut bookdone.azw to your 'drm free books' folder you made somewhere else and delete the book1.azw file if you like
6 - open
Calibre, add bookdone.azw to your collection, connect kindle, add bookdone.azw to Kindle main memory
7 - done
Or at least, that has worked so far.