I like the idea of Knowledgeroot, and 0.9.7 works nicely. But the WYSIWYG editor gets in my way.
Oh yeah, it's FCKEditor alright, in all its glory and massiveness, and a bug to bug implementation, too (well, that's not your fault, surely) - why not use something smaller like widgEditor? After all, this is not a content management application, presentation is geared towards organisation of information and not attractiveness. I'd leave that part to the admin/designer entirely. Showing all those controls invites all sorts of misbehaviour from ignorant users (I'm speaking as a CMS admin here who has to clean out rotten layout and content time and again).
Using WYSIWYG is sensible, though - either that or some sort of BBCode instead of HTML in order to prevent people from having to add basic page structuring like paragraphs or even linebreaks. I know some blogging applications that are using BBCode - it's a nice and quick way of formatting content without WYSIWYG or HTML.
Knowledgeroot seems pretty straightforward - tree structuring of content is helpful in many cases, and the handling of content is well thought through.