flash actionscript: if (_root.ball._currentframe == 44) {
gotoAndPlay("lv2");
}

is gotoAndPlay("lv2") trying to make the root timeline play from "lv2" because
I think that's what it's doing.

If you want the ball to go to "lv2"

then you'll need this..

if (_root.ball._currentframe == 44) {
_root.ball.gotoAndPlay("lv2");
}

I'm afriad I'm not too sure what the problem is. But I'd attach the script as a
movie script to the ball movieclip.

Then add an onEnterFrame event and place the if statement inside. I'd possibly
suggest that the if statement is only being called once, rather than being
called every time a new frame is entered, so it will never evaluate as true.

Hope that helps