You are using Windows, screenreader? If yes, try
Manga2Ebook - if you're using Linux, you could try my Bash script which depends on the GIMP, ImageMagick and libtiff (the scm file goes into GIMP's script folder and the gpl file into GIMP's palette folder).
I didn't try Manga2Ebook, but my script produces good PDF's which work great with the Cybook. Page turning is sometimes a bit slow, but that's the only problem I noticed.