Custom columns don't copy on create new library
1. create a new library - Library A.
2. add a couple of custom columns 'location/Location' and 'tariff/Tariff' (screen shot 1).
3. restart calibre
4. create another new library - Library B using on Library A's structure (screen shot 2)
Library B does not inherit the custom columns
I think it's something to do with Library A being empty and never having had any books in it.
I used a fresh install of v 2.71 portable to do the test.