AS3: stage align TOP_LEFT, resizing mc hits the top right corner

Full-screen flash site has stagAlign.TOP_LEFT, works fine, yet when I add a new MC to the center of the stage and resize it (TweenMax scaleX, scaleY) it hits the top and left corner and is pushed from that point. How do I go about allowing the new MC to extend the stage align. Resize MC with disregard for the stage’s top left corner. I can center and resize the new MC fine but it will always hit the top left, and I would like it to extend the visible stage. Refer to attatched

Any and all help is as always greatly appreciated.

Thanks…