Rain Animation problem

I was trying to use a rain animation available in the movie section of this site. The code is as follows:

Action Script in 1st frame

Code:

---

cont = 1

---

Action Script in 2nd frame

Code:

---

gota.duplicateMovieClip ( "gota" + cont, cont );
eval("gota" + cont)._x = random (550)
this["gota" + cont]._y = random (400)

cont++

---

Action Script in 3rd frame

Code:

---

gotoAndPlay (2);
if (cont == 30) {
        for ( numero = 1; numero <= 15; numero ++ ) {
                removeMovieClip ( eval("gota" + numero) );

}
gotoAndPlay (1);

}

---

The animation works fine but I was trying to use it on a 1000 or so frame timeline with the idea being it runs for approximately 100+ frames and then the rain animation ends yet the rest of the movie still continues forward on the timeline.

I'm using Flash MX 2004 (no funds for an upgrade at present)

I see how this is looping back to frame 1 ... gotoAndPlay (1);
but I'm not sure how to alter it.

Thanks.