Hello,
a 400 page book (no epub format available), bought from Amazon deformats to more than 900 pages, hard to read. The index alone is stretched from 20 pages to 30 pages. For a sample page please see the two appended gifs.
The grey background could be avoided with the elder version 3.23. (hint of another post). I also tried on-line conversion tools (cloudconvert, freefileconvert, epubconverter): one with the grey background, all deformated.
Any help welcome!