SwapDepths and gotoAndPlay Movie problems

I am trying to get a FLA to work correctly. I have 4 movies that I want to play with a navigation swapping the movies to the front as clicked. When I use the navigation, the first few movies work great, but as I click through they start to get a little jumbled, and it breaks.

I am using this script for the buttons to call on the movies:

on (release) {
//x +=4;
_root.Movie_Working.swapDepths(+4);
_root.Movie_Working.gotoAndPlay(2);
_root.gotoAndStop(“Working”);
}

I would think this would be simple enough, but its cracking. Can anyone give me a clue on what I am missing in my script? I have tried this 3 different ways and its coming out the same. The file is too big to upload (2,200kb), but if anyone wants to take a look, please email me.

Thanks in advance
Eric
eric@sputnikk.com