Document Formatting Corruption Issue - Urgent Help

I've spent hours working on a document in pages that has a mix of varying text formatting, image positioning (Inline, floating, in background), tables, shapes, grouping, page breaks, lists.... it's a slight mess.

Didn't start having this problem until recently, something that I have changed in the document now causes this to happen:

I add some text to a certian middle page in the document, and save it. The document appears in perfect condition while I leave Pages open, as soon as I Quit the application and restart it - some (lots) of my images and grouped shapes (diagrams) shift up the document, overlapping and underlapping text and causing images to disappear and it becomes a mess of colorful nonsense.

I've tried clearing the Pages preferences, copying and pasting certain bits in different ways - but I'm really lost as to what could be the issue.

I have to finish writing this very soon (2-3 days MAX) and I can't continue while it is messed up like this - and it is far too long to retype into a fresh document.

I've tried 'sorting' the mess out, but it's hopeless because it all gets messed up again as soon as I restart the app.

This is Pages '09 V4.3

Any suggestions are greatly appreciated.

THANKS.