Hi,
I'm not sure if I understand your requirements correctly, but you
should be able to get it to work without setting a size for the header
at all. If there is no size, it will automatically take the size of
the child elements. If those change, you should recalculate the layout
and the size of the header should change accordingly. If you like to
have a minimum and maximum height for the header, you can set this in
the CSS, and the plugin should take that into account. Manually
setting it---as you suggested---should also work of course.
If I misunderstood your problem, could you please provide a simple
example, and hopefully I can help you further.
Bram