Hi,
I was really interested in reading the "readme.txt" of Ditherig.exe, so I autotranslated it (via Google Translate) from Japanese to English, and published the result here:
https://logixoul.github.io/ditherig-english-documentation/
(the copyright is respected, as the ditherig.exe author has published his sourcecode under the MIT license, and this includes the readme.txt)