Problem unloading external swfs

I have several buttons in my cbtLoad layer (5 buttons) that are used to load external swfs into a movieclip holder for playing.

these all load fine and play. BUT when I press another button to load another swf in the current one’s place, nothing happens and the current swf keeps playing in a loop.

I need to have when a button is pressed the current swf stops and the new swf plays. Also I need these to not loop. one play through and then they either pause until a new button is pressed or they unload at the end of play, automaticly.

Any suggestions?

Here is the ActionScript that I am using with each individual button on the cbtLoad layer.

on (release) {
if (_root.currMovie == undefined) {
_root.currMovie = “external movie”;
container.loadMovie(“eternal movie.swf”);
} else if (_root.currMovie != “external movie”) {
if (container._currentframe >= container.midframe) {
_root.currMovie = “external movie”;
container.play();
}
}
}

What code am I missing here? Thanks.