It looked to be one of the first rough edits they had made of the film - wish I could remember more about it, but only saw it the one time. If you have ever seen rolls of film dailies befoe, this is what this version looked like - a bunch of film dailies edited together complete with the dailies audio - no sound effects or soundtrack music had been dubbed into the film yet.
I will NEVER forgive myself for not copying this onto a VHS while my boss wasn't looking.....
The Dune cut might have been the first edit of the Alan Smithee cut which Lynch had been dead set against - because after seeing that version last year on a full-screen DVD-r, I recalled a lot of that footage from the edit we found. So I am led to believe that it was simply an early version of Smithee's project.
Hope this helps...sorry I don't have more info for ya!