From last night and the off-line communication we had, posted here for the benefit of others.

In the spec you provided, there was a horizontal line with width 0 hiding underneath the Last Page Footer grey bar. This was only located when the grey bar was moved up without the objects and then 'Select All In' to select all object and see the invisible object.

Removing this line and putting the grey bar back into position seems to have fixed the issue on our end. We await good news from your side.