[Zubersoft]

I know I already answered your email, but I'll post the answer here for the benefit of any other users:

A "blank page" isn't tied to any file at all. It's just data in the database that instructs MobileSheets to display a white rectangle for the page instead of something from an actual file. Annotations on the blank page are stored in the database. If you export the song containing the blank page, then a PDF will be generated.

Mike