Game Help(Arrays and Collision)

Haven’t seen anything that forbids help topics, so here’s my problem. Any help would be greatly appreciated.
I’m trying to get the collision to work (for five hours), I started out without the array and someone helped me out and said that arrays were needed for the enemies. So, I put the array in, now there’s a problem with “enemyarray.push(Enemy)” that outputs :

TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Game_fla::MainTimeline/spawnEnemy()[Game _fla.MainTimeline::frame1:27]
at flash.utils::Timer/_timerDispatch()
at flash.utils::Timer/tick()

Many times.
And many times more.

The Game: [COLOR=#800080]http://www.trportfolio.net/upload/view_u pload.php?id=20102[/COLOR]
-When missles and enemies collide, they’re supposed to die.
-Not actually what happens anymore, broken now.

Attached the file. Thanks to all those who try.