Tags wrongly used when converting a FrameMaker book to plain HTML (FM 2017)

When I open a single document and use the Save Book As and select the HTML option, the Paragraph Styles are rendered in a logical manner - Body becomes 'P', etc. If I do this for a book, Body becomes H4.

Also, when a book is selected, I have no access to the HTML setup options in Utilities, so I can't customise my output.

This happens with both FrameMaker 2017 and FrameMaker 8.

I realise that this part of FrameMaker is rather ancient (the documenation talks about using Netscape), however for the project I'm working on, the single HTML document output is potentially very attractive.

Is there any means of controlling this output from Book format?

Thanks,

B Wilkinson