I have created a few landscape reports -- one quite wide, but one in common paper size.
However, when the viewer opens, it is too narrow. I have been unable to figure out which settings to change to make the window open bigger.
The attachment shows how it is opening (left side) verses the width I'd prefer it to open as (right side).
I suspect an edit to the XML files may be in order as changing any of the other values via the properties isn't working.
The report in question is intended for standard US "letter" size paper in landscape format, or 9 inch display excluding margins.