You can download the PDF from
ImageIngester.com/ImageIngester/pubs/II-Manual-Draft-01.pdf (about 3MB).
Still incomplete and unpolished, but much better than what's been on the web site until now.
It's for ImageIngester 2.x (not yet released) and ImageIngesterPro 2.x (in beta for Mac and Windows), but much of it applies to ImageIngester 1.x as well.
Comments on its general approach are welcome, but detailed editorial comments probably should be deferred until I've had a chance to work on the draft some more.
--Marc