[Joques]

DiapDealer, back then I unencumbered my epubs with a commercial program that actually messed up my files in some very subtle ways (i.e. caused a weird but fixable compatibility problem with the "Kobo extended features" Calibre plugin), but nothing like this ever happened. I am always very particular about keeping the newly unencumbered files separate in their pristine form, and I only ever mess around with copies of the files. So I can fairly confidently claim that I didn't do this :-)

JSWolf, cool to hear you confirm the error.