Hi,
Just downloaded and tried the latest version of Publisher and found that when I import an IDML file there seems to be no stop on the scrolling beyond the pages area.
The scroll bars at the side of the page also disappear when they get beyond the edge of their position.
There should be a limit to how far you can scroll beyond the page area, it seems that this is missing.
attached are the InDesign IDML file and the APub file.
Hope that helps.
Cheers, Steve.
Cheltenham Races Refund Envelope.idml
Cheltenham Races Refund Envelope.afpub