Graphic added over button is my blocking MouseEvent why?

Answer 1

you didn't post how you're instantiating 'closeTabX' in the first example, is it the same class as the smaller example(CloseTabX)?

A simple 'fix' is that if you set it's properties as follows it will not block mouse events to it's parent:

closeTabX.mouseEnabled = false;
closeTabX.mouseChildren = false;

If that class is never intended to be a mouse target, you could also set these properties in the class constructor to prevent any instances of that class from blocking mouse events.