Hi Alec,
Thanks for your inquiry.
The issue is currently being looked at, we will inform you of any developments. In the mean time you can avoid this exception by avoiding using frames in your document, more specifically using textboxes within frames. You could also avoid this issue by removing your call to UpdatePageLayout. Is there a specific reason as to why you need to call this method with this document?
Sorry for any inconvenience.
Thanks,
Adam Skelton
Programming Writer
Aspose Auckland Team