To create reports using custom paper sizes, set the Layout.PaperSize property to System.Drawing.Printing.PaperKind.Custom, then set the Layout.CustomWidth and Layout.CustomHeight properties to the size of the page measured in twips.
If the Layout.PaperSize is set to a value other than System.Drawing.Printing.PaperKind.Custom, the paper size is determined by that setting. The Layout.CustomWidth and Layout.CustomHeight properties are not used in this case.
If the Layout.PaperSize is set to System.Drawing.Printing.PaperKind.Custom and the Layout.CustomWidth or Layout.CustomHeight properties are set to zero, the printer's default paper size is used.