In this form, one can change settings for scaled printing, before the print is initiated with OK.
Here one can enter the scale, e.g. 1:200.
This button opens the Printer-Setup dialog.
Here, the image size on the paper will be shown.
Paper Size of the currently selected printer minus hardware margins.
Here, one can enter the margins. The buttons Center calculate the margins for centered printing.
The button OK is available only, if the image fits onto the paper!