Hmmm. That's what my grandma would call a poser.
Is there anything unusual about the fonts or characters in the book? Is it unusually large (like over 5 MB)?
The only off-hand suggestions I can think of is to see if it works as an RTF, or to try converting it with something else such as
BookDesigner, just in case it's some sort of obscure conversion quirk in libprs500. But both of those are just random thoughts, not really based on anything.
