Problem with get url

I created 4 layers:

layer (actions): with a ‘stop’ function in the first and 12th frames, and gotoAndStop(1); in the last 31st frame.
layer (labels): have no code, only frame titles “over” and ‘out’
layer(layer2): its MC in motion tween
and layer (invisable butt)’ which has this code below

on (rollOver) {
gotoAndPlay(“over”);
}
on (rollOut) {
gotoAndPlay(“out”);
}

and now when i convert this MC clip in a button and add get URL command then motion tween animation doesn’t work. also i will be loading external swf with the same butts. any clues?Please

any suggestions will be so much appreciated