The numbering will change from ODF 1.2 to ODF 1.3.
> and the low numbers are missing. Is there something similar to the ZIP-file
> OpenDocument-v1.2-os.zip (of course, the version 1.3 and perhaps draft and
> the date or a subversion number in it)?
No zip. They are working drafts of the committee.
For header/footer topic you need 'part 3'. 'part 4' contains the formula
language for Calc. "production" in the file name means, that it is a version
without change tracking. Take that with highest wd-number in the filename.