Hi,
I've recently worked on a project similar to your currnet situation. I won't say it's impossible, but -as I understand- you'd like to have an HTML editor in Flash.
Let me say it's a better (and comfortable...) idea to make such an editor out of a mix of technologies. We did it in Flash+HTML. Needs some javascript, but Flash is smart enough to do some parsing jobs on the files or variables, too.
And (let's say) more compatible on cross-browser issues than javascript can be. (Netscape vs. M$ for example...)
Sorry, but I don't own the sources 🙁((
Best
Paul