The newly introduced pixel value view does not react on the crosshair change inside the mxnMultiWidget.
This is due to the use of the QmitkSliceNavigationListener which only reacts if the corresponding slice navigation controller of the render window, where the user has clicked into, has changed. However, for the mxnMultiWidget widget the slice navigation controller did not change since the slice did not change on a crosshair selection change. Only the two other coordinates for the crosshair planes changed but the view stayed on the same 2D slice / plane.
(In the StdMultiWidget case the two "orthogonal" planes and their slice navigation controllers (rather their slice steppers) changed and thus the GeometrySliceEvent was sent).