I'll look at it when I get a chance, sure. It may be a day or two, it's harder to reproduce bugs like that with a baby in one arm
That window you get when you customise the KoboTouchExtended plugin is the driver settings window. One of the check boxes there is 'Hyphenate Files'; if it's selected I add hyphenation CSS (but I do not modify what's already in the book's CSS), if it's not selected I don't touch hyphenation at all.