This function is similar to , and the alternative method of invoking it is by placing the mouse cursor over the node and pressing the F4 function key on your keyboard.
If you create a variable node and then decide that you'd like it to be an asserted molecular node instead, delete the node and redraw it instead of calling on it. Should you do the latter, the displayed node will ``look'' asserted, but internally will still be marked as a variable node and cause problems.