You can open any .htm, .html, .xml, etc files there... it has Designer and Coder views... I use it more to edit static content rather than dynamic. I edit or creat, then copy the code and finally paste it in Joomla! As Dreamweaver creates styles for the content in the same page, you copy/paste that, too, and Joomla! understands it as HTML.
I don't understand your question. Static content is any content that is written within the code. Dynamic content is the one that is called from another file or database.
I want to create a static content item that I can add HTML code to but when I use JCE and paste the code into it and then save, refresh my page the code changes from this
Both codes are calling the same file. If your URL dissappears because of your live site, it is the same, so images/ is the same as yourDomain.com/images/
Your content appears the same, offline and online?