I found your question here as i am browsing over some doop related articles on the net.
So, re: your question, yes the only effective way is:
– configure .htaccess file to treat .html as a .php file and execute codes.
– make an include page like you mentioned above.
* Version 2.0 (soon) now uses this kind of method for security and web standard purposes.
Send me your file so I can check what’s wrong with your sample work, the email address is on the site’s help page.
Sorry, our forums is still in the works. but I will be soon having a blog as an alternative for doop support old and new versions