Is there a simple method to convert WebSpinner styles into something DreamWeaver can manage in a similar fashion?
Yes. If you set up a ‘site’ in DreamWeaver for your Web site, giving it the domain name, etc., AND you download the /.stylelist/ folder locally, DreamWeaver will show the headers and footers automatically (for any file that uses them) in its preview screen. Note that if your users have permissions that exclude the .stylelist folder, they won’t see the headers and footers.