I'm sorry for the very quick "haven't even read the post thoroughly"
response, but I'm panickingly getting ready for a trip. Just glancing
at the content model Laurent posted, this looks an egregious,
easy-to-fix error to me (that "?" should be a "*"). I will try to
take a more careful look and hopefully repair before Monday.
MB is raising a slightly different issue, which I will also try to
look at before Monday, but without the high hopes of easy success I
have for Laurent's complaint :-)