The book-export is not a general exporter for all pages, but exports only pages with a page_order attribute (in the edit-form the field called "section"), which have as well the publish_status "ready" (in the admin/list, publish has green symbol). These pages can be transformed into one html-page using the prototype page book-print (if you instance is called /wiki, type /wiki/book-print).
Save the page generated page and edit as desired (e.g. adding style-files, adding more info, etc.). You can also make your own variant of the book-print page, which can be found in packages/xowiki/book-print.page). The single html-file can be converted to pdf using the usual html-conversion tools, or can be printed into pdf.
For exporting all pages (e.g. exchange between instances), use the export functionality in admin).
-gustaf neumann
