The author gave credit from Kupu's credits file, which was (sorely) missing a key contributor: Duncan Booth, now working at Oxfam Great Britain.
After Philipp did the initial Plone integration, Duncan took over and did a tremendous amount of very, very high quality work. The configlet for the Plone control panel is the best for any Plone add-in that I've seen. Duncan also did the zoom mode, rewrote my browser-side Word->XHTML cleanup, a link repair approach for content types, ongoing bug fixing, and more. Plus he answered every question on the list.