Responsive HTML5 using Multiple Books - issues with heading levels

[KrisZ]

I am trying to create a singular HTML5 output that is a combination of 3 book files (one 'master' book with 3 child books). When I do this the heading levels in the TOC pane are not respected resulting in a flat (non-indented) output. Also, the autonumbering is omitted and the topic names list the file names instead of what’s written in the FM files.

Now, when I create HTML5 output on each individual book, its formatted correctly (headings, autonumber, etc.) and the output looks great; its only when I add each book as a child book and then create the output using the 'master book' does the TOC pane not have the correct heading levels, autonumbering, file names.

The source file are in FrameMaker unstructured format. The books are made up of Chapter files, an FM generated TOC, and Index. I'm also using a CSS file for automapping the styles. We are using FrameMaker 2019, latest build.

[Jeff_Coatsworth]

I suspect that trying to publish HTML5 directly out of FM with that book-of-books structure isn't handled well enough (I use it too with 60 child books in one of my projects). I only managed to get output created by going the FM > RoboHelp import route and generating from there. The ability to tell the output generator what TOC to use (like RH does) is the key - FM doesn't seem to have that feature in its publishing settings - it seems to rely on font size and indenting to figure out what to use for the resulting TOC in the output.