From OpenSCADAWiki
You can place the added items as you want by simply selecting and dragging them by the mouse. In the same way you can change their size. Simple size changing will only resize the container widget geometry, that often not required. To change the size of the entire widget's content, it must be scaled by holding down the "Ctrl" key while resizing or by switching the "Resize" status to the "Scale" in the status bar.