Pretty cool, Skrommel!
I suggest you try the app skrommel mentioned.
Even though it consumes more memory and doesn't allow buttons to be dragged out of the start bar, it is way more updated (still maintained!), has support for groupped windows and has a feature that was requested some time ago here on DC as a coding snack: close a window on middle click. (oh, and did i say it looks good?
It has no love for GridMove, though... Might be time to update gridmove..