[Agama]

Well that seems to work. I have switched off wifi and deleted all collections one by one. It nagged me each time that I was offline but still let me delete them. Then I created my new collections, (with more nagging), and finally I selected "Show only in collections view". I've put some books on via calibre and this works well, apart from not adding them to the collections but this is easy enough manually. One oddity that I've noticed is that the Kindle User Guide, which I've put in the Reference collection, has an asterisk next to it.

So thanks for the helps, my Kindle is now tidy and free from cloud collections.