MFC version

Note that if you press the down button of the layer input (Lines tab) while the subgrid is activated it gets in a bad state -> displays -1 and can't be changed.
Qt version

Note that all the activate checkboxes are enabled on the Qt version
Also note that if the down button is pressed on the layer input it asserts (This occurs after the subgrid has been activated/deactivated).
It seems that the Qt dialog needs quite a bit of work for DISV grids