I need help with code modification

I need to modify the code from here: http://www.freeactionscript.com/download/as3/realistic-floating-soap-bubbles.zip
You can see it in action here: http://www.freeactionscript.com/2010/08/realistic-floating-soap-bubbles/#comments

What I want to do is change the size of the balloons (increase it).
I made some modifications in Bubble.as, I changed the _container.scaleX = _container.scaleY but didn’t work.
Also change the image size itself but nothing.
Can someone help me?

Thanks