Setting up a paper size to A1 and exporting the document actually sets the paperSize to 1. 

This leads to inappropriate values when entering the Page Setup options later in Excel.

If  row has a property set on it (for example "hidden" or a style), but it does not otherwise have any cells in it, the application might run into an infinite loop. The xml will look like this:

	<sheetData>
		<row r="1" spans="1:2" x14ac:dyDescent="0.35">
			<c r="A1"><v>1</v></c>
			<c r="B1"><v>2</v></c>
		</row>
		<row r="2" spans="1:2" s="1" customFormat="1" x14ac:dyDescent="0.35"/>
	</sheetData>

The last row has formatting applied, so it is present as an element, but has no cells. This file (when the xml is not formatted) will cause an infinite loop on import.