Suggested text addition to the help somewhere on this page from Dave Stamm over on the Framers mailing list:
In a structured book, in the Structure View window, the program displays the top-level element in the book as <NoName>.
The parent element for the book is not applied to the top-level element.
1. After adding structured files to the book, update the book. In the Structure View window, the program displays the name of each top-level element in each file. The program displays the top-level element in the book as <NoName>.
2. In the Structure View window, choose <NoName>. In the Edit Attributes window, on the Elements tab, choose the Options... button. The Set Available Elements window appears.
3. In the Set Available Elements window, in the Show Tags For: area, in the Valid Elements for Working Start to Finish option button, ensure a dot and choose the Set button. The program sets and displays the available elements.
4. On the Elements tab, choose the top-level element for the book. The program changes <NoName> to the name of the chosen element.
5. In the Structure View, arrange elements to conform.
Again, many thanks to Rick Quatro. As many others have written before, "¡The contributors to this list are the _best_!"