die-computer-spezialisten.de: Newbie needs to understand something

I'm using Mac OS 10.5.8, Word 2008, and Calibre to prepare an ePub for upload to PubIt for the Nook and iTunes for the iPad. The ePub file I've created is viewable with absolutely no formatting errors of any kind on my computer with ADE, a Nook, and an iPad. But when I try to deliver the file ...

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