I’ve noticed that it’s not possible to have multiple pages in one document with different canvas sizes, as an example I have the same design in 4x4", 6x6" and 10x10" and I want them in the same PDF.
The feature has been requested:
Bug 49787 - Formatting: Allow different slide / page styles (orientation, size) in a single Drawing document
The only workaround is to use separated documents, one for each page, and then merge the resulting PDFs using an external tool such as PDDtk or PDFsam (both have open source versions).
I think embedding OLE draws in Writer or calc, could solve the issue.-