In that case, is any way to find out what nodes have been ch

In that case, is any way to find out what nodes have been checked through this
automatic checking process? Pertaining to one of my previous emails, I need to
check other nodes with the same value as anything that has been checked (my
tree has duplicate elements throughout).

There is no way to detect that node was
checked or unchecked automatically by parent checking/unchecking. But you can
consider that if node is checked -
then all child nodes are also checked.               

function
on_check_hand(id,state){

                //actual oncheck code
                …
                //virtual oncheck for child
items
                //get array of direct childs

                var childs=my_tree.getSubItems(id).split(",");

                //call same handler for all
childs

                for (var i=0;
i<childs.length; i++)

                               on_check_hand(childs[i],state);
}
tree.setOnCheckHandler(on_check_hand);