Button doesnt work behind a movieclip

Can someone help me with this problem? I’m not quite sure if my actionscript is affecting it. How can i code it in such a way tat my button would trigger the gotoAndPlay()?

Source file:
http://s18.yousendit.com/d.aspx?id=28HOAGBWBZEGZ0T3H3JXY2K51F