Adam,
I tried to do what you outlined but it did not function as expected. I set multiple CSS files separated by a comma and it the editor itself had the properties in it - but nothing was in the class dropdown.
Also - can you provide someway of disabling the "body" tag is css files that are set to the editor - or make the body tag only applicable to the first CSS file assigned? I want my users to be able to select the styles in my global sheet - but not have the editor window show the solid color for the page.
regards,
Dave