When the name of rectangle object is ZOOMRECT,
1. open Object Properties dialog should go to Dimensions tab by default.
2. Unit should be Scale by default.
For Rectangle/Circle/Polygon/Polyline/rake object,
1. Unit = Scale, show Right and Bottom editbox instead of Width and Height.
2. Unit = % of layer or % of page show Left Margin, Right Margin, Top Margin, Bottom Margin.
Add Update Dimensions to context menu of Zoom ROI, above Properties. Click it could get the scale info of related enlarged graph.