An ugly work around is to set the length of the page to a very high height. Go to Format -> Page Format... in Height enter 500 inches (36,000 pixels, 1270 cm, or 12,700 mm). If you still have problems double this value and double again if required.
I found the same issue when creating a report and didn't allign the text boxes perfectly. Any missalignment, even by a single pixle, will add extra tabs and rows.