Is this what you want? I didn't look at your patch much, but it seemed to be buggy (reset the 'parent' to 0 when I moved a child).
AFAICT, my patch has the behaviour you want in a suitably simple form. Things do get frustrating when a simple function turns to spaghetti, don't they.
hi again maybe a simple question... i am trying to build up a parent-child relationship between two or more sliders (for ex. 3 child sliders working independently. if i move the parent slider all three change their values according to the parent slider, up from there last values.) i am getting more and more confused and it just wont work up....