My guess is that the <?pagebreak number="2"?> tag is your problem. That does not appear to be the standard method/tag to indicate a page number. Perhaps it is a software/reader specific tag??
In ePub3 it should look something like:
Code:
<span
epub:type="pagebreak"
id="page24"
title="24"/>
ePub2 typically used the <a id="p2
"/>
(correction added) as a symantically
incorrect workaround.
I would do a search and replace to remove all instances of the <?pagebreak?> tag...of course, make a backup first just in case...
