Something is amiss in your large xml block. You have:
<div xml:id="VS1" n="I" type="book"> <div xml:id="VS1" n="1" type="chapter">
but that is two identical xml:id fields, which can't be right .... Taco
thanks, you are right of course! I was missing one level of the structure. Am working on it, but on the train, so not logged in.