I think I did find a bug and not sure when or how it got there. It will be fixed in next version (along with some other book script improvements currently in development). In the mean time, you (and others using this script) should be able to fix it as follows:
1. Start GEDitCOM II
2. Hold down option key and choose Reports->Generations LaTeX Book from the scripts menu. This step will open the script for editing in the GEDitCOM Editing
3. Do Command-F (i.e. Find Command) and search for the text "treePerson(pppp"
4. Insert the following line just below the line found in step #3:
treePerson(pppm,4*hlen,29,True)
5. Make sure the indent to the start of this line is EXACTLY the same as the lines before and after it (a Python requirement)
6. Save the script
7. Go back to GEDitCOM II and try your book
Let me know how it works.
Thanks,
John