I am anxiously working with Edge Animate and very excited at the prospect of what it has to offer. However, I'm running into problems working with existing HTML files. Specifically, when I open an HTML file created outside of Edge, I've noticed that elements such as div's, etc are set to "static" and not "managed". Thus, I am unable to access some parameters, like setting x/y and scale to percentages. Also, the stage is omitted and I can't see how to add a stage. I assume opening an HTML file and developing with Edge is not the way to do this?
If you open an existing HTML, it will use the structure of that file and will try to keep it as close to its original state as possible, as you may have added CSS formatting to the div that we don't want to overwrite. Thus, it becomes a "static" item instead of a "managed" element. You can create your own managed elements on top of a file that you open by drawing rectangles/roundrects/ellipses (a div), adding text, or importing images to the stage, and all of these elements will be able to be changed using the controls in the toolbar and properties panel.
Hope that helps.