UPDATE: I changed one of the level 2 headings and now the book is publishing correctly. Sorry for the bother.
Suddenly, the generated Word document no longer contains a book title, although the topics are there. The books before and after publish correctly, as does the web help.
I seem to recall a piece of rogue code causing this sort of problem but I cannot locate that thread.
I should add that I have already done the following:
Any help is appreciated.
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