Enemy help

1

Hi, I’m pretty new to flash, and I have to create this game for my digital imaging class. So far, I have the code below, but there are some problems I’ve encountered. The enemies need to fall from the top of the screen randomly. I also want to change the speed of the enemies to make them fall faster and in greater quantity. Lastly, I am trying to make a different scene with a separate enemy coming from the top, but every time I change the name in the parentheses to the instance name of the new enemy, it remains the same! Any help would be amazing! Thanks.

 
 
 
shanemc._x = 1;
onEnterFrame = function() {
shanemc._x = shanemc._x + 0;
if(shanemc._x > 500){
shanemc._x = 0;
}
if(shanemc._x < 0){
shanemc._x = 500;
}
if (Key.isDown(Key.RIGHT)) {
shanemc._x += 8;
}
if (Key.isDown(Key.LEFT)) {
shanemc._x -= 8;
}
 
 
 
 
var enemyStartPoint = Stage.height+400;
 
var enemyEndPoint = 0;
for(var i=0; i<enemyCount; i++)
{
    var enemy:MovieClip = _root.attachMovie("enemy", "enemy"+i, i);
 
       enemy._y = enemyStartPoint;
 
        enemy._x = Math.random()*Stage.width;
 
      enemy.enemySpeed = Math.floor(Math.random()*3)+2;
 
 
    enemy.onEnterFrame = moveEnemy;
}
 
function moveEnemy()
{
       this._y -= this.enemySpeed;
 
        if(this._y < enemyEndPoint)
    {
 
        delete this.enterFrame;
 
                this._y = enemyStartPoint;
 
 
        this._x = Math.random()*Stage.width;
    }
}
}