Chris
I have emailed you back the corrected file.
There are several problems with your document, but the principle one is that you tried to do it using the wrong template.
For a fiddly layout like this, with lots of rotated objects and textboxes, using the Blank Word Processing template is bound to lead to problems, when you can't follow what is going on.
Word Processing templates flow text from one page to the next and retract when there is no text on them. Think of them like a scroll of connected paper that runs from the beginning of the document until the text runs out.
That scroll ignores any floating objects on top. Wherever the text runs out that is the end of the document. The floating objects are still in the document but can end up on pages that are no longer being displayed.
You have a large number of assorted floating objects, images and textboxes which seem to have text wrap on them, which combined with the background image which also has text wrap on, causes unpredictable results pushing text off one page and onto the next. You had invisible characters, either returns or breaks that were forming pages that you then added the background and floating objects to.
The last section break was pushed off the prior pages by the full page background's text wrap causing the blank page the section break was on plus the next page it broke to.
When you deleted the Section Break, the Word Processing scroll dramatically shortened to the last previous character, 2 pages back, and no longer showed the pages in between with the floating objects on them.
There were also other problems.
1. The background graphic is much too low resolution to fill the page and is distorted, but I guess you can live with that.
2. There was text that had overflowed some textboxes and was not showing
3. The background was interfering and getting in the way of everything above it
Rather than try and totally unravel this knotted ball of string, I have severed the Gordian knot and reconstructed the background as a locked background in a Page Section in a new Layout mode template. Then I grouped and copied over the floating images and textboxes. To the exact same positions as in the old document, fixing the overflows.
The Layout mode will be less confusing for you as every page is its own section and stays visible even when blank. There is no page to page flow to stuff things up.
You will find the master section for the "Parchment Page" under the Pages icon on the Toolbar. If you need more of those pages just click on the icon and select another page.
Peter