In 2014.10, the support for different level windows in different renderers doesn't work anymore.
The reason for that is that the level window filters in different renderers share the lookup table by pointer, but they all modify the same lookup table by setting the range using their own level window. Thus, if mapper for one of the renderers is updated and it is not for the other (for a reason that nothing "apparently" changed - see the Update() function of vtk image mapper 2d) - the incorrect range will be used by the vtk pipeline.
So either the lookup table property value should be DeepCopy()-ied for each renderer, or some other approach should be used to prevent this. I would say that every SetLookupTable() call in mitkImageVTKMapper2D is not correct in this regard.