This is really old, but I was trying to use this and keep getting "An error was found in the format of this document." on my NSpire.  The ebook.exe works fine, no errors.  The document transfers fine, too.  The problem happens when I try to open it.

The weird thing is I can open your sample book.  It works just fine.  The problem is none of my books seem to work!  Just wondering if anyone else had a similar issue or can offer any suggestions.

Sorry, I realize this was really old,
 - gfrung4