HTML is currently in a state of flux. HTML 3.0 has been proposed for some time now, though nothing has been formally implemented. PageMill supports some, but not all, proposed HTML 3.0 tags and Netscape extensions. The result is that you may find your existing pages splattered with red 'raw HTML' coding when you open them up in PageMill. The biggest disappointment of all is the lack of support for HTML tables.
Tables are both difficult and tedious to code by hand.
This has been the major criticism of PageMill so far, and one I expect Adobe are addressing with urgency. Also, though I have not experienced the problem, many HTML authors on the Internet have remarked that PageMill can implement HTML in a non-standard way that will not layout properly in any other Web browser except Netscape Navigator. However, PageMill doesn't aid the creation of the CGI scripts, the programming language in the background which controls the form. Information about script creation is beyond the scope of PageMill and this user's guide, so you'll probably need some technical help to create an action script for your form. As there are already applications in existence that will help create and write CGI scripts for you, I hope this is another shortcoming Adobe are looking at.