Hi Sundance.
Re. upgrading, I actually do the reverse - make a complete copy of the retiring Zorro folder into a new one, and then install the new Zorro into that new folder.
Re. upgrading & Margin, to continue with the same CR the correct new Margin needs to be determined by Testing. I was wondering if not doing that and continuing with the old version's Margin setting would have produced this kind of situation? A question for jcl...