SAB 9.2 MAC - more flexible HTML menu required

The HTML generated by SAB gives the user the possibility from a simple list on top of the screen which book he wants to read. This is generally sufficient, but in our case we have not a few front matter books and the 66 bible books, plus 66 ‘commentaries’ plus an increasing list of articles concerning various topics. The list becomes too long.
The best would be to have a simpler structure first like:

  • introductory books
  • bible books OT
  • bible books NT
  • bible book Introductions
  • topics
    After clicking one of these, then the books of that kind would be displayed.
    I am willing to adopt this file manually each time before I upload a new set (if not too complicated) but I have no idea if there is a way in HTML to get setup as described above.
    You can find the sw.js file that regulates the menu in this link, so you can see what it is about:

Also, it would be great if SAB could also pull the data from the “About” page, which usually contains copyright information, and make it a separate HTML page. Otherwise this information is not available in the PWA presentation of the build. This page could be added to Joop’s list at the top, bottom or made to be the first page a user might see.