How can I upgrade all my Pages '09 documents to Pages '13?
I was able to fix this by doing the following steps:


Create a new pages document, and just throw in whatever text. Save it.
A .pages file is actually a .zip file, so right click on that and unzip it.
In your 09 pages file, right click and select "Show Package Contents"
Copy everything from the Index directory of your 09 pages doc to the Index directory of the new one.
Zip up your new one, the one you unzipped and copied in the 09 index files.
Rename the zip file you just created with a .pages extension
Open in pages.