MIDAS multi widget zoom around crosshair, not the mouse position
The zoom interaction should be changed so that the focus point is the cross hair, not the position where the user starts the zooming. (The initial mouse position of the mouse move with right button.)
Also, at the start of the action the crosshair should be put to the mouse pointer. This guarantees that the crosshair remains in the displayed area during the zooming in each render window.