Problems setting up collision with new object

Hi guys,

I'm developing a shoot 'em up game where if the player kills enemy, the enemy turns to a block (block is a new object replacing enemy - enemy is removed from the stage) and the player will be able to push the block around the level.

For some reason, I can't seem to setup the collision on the new block object that appears on the stage, I using the same code structure/idea for bullet detection on enemy but doesn't seem to function. I was wondering if anyone would know what I'm doing wrong or any suggestions to fix/work around? Here goes....

I have 3 classes/documents -

Block Class - Properies for the block object
Main Class - logic and core features of the game
Collision Class - Collision properies and setup

- Block Class -

Code:

---

private function onEnterFrame(event:Event):void
                {
        MovieClip(parent).checkCollisionWithPlayer(this);
}

---

- Main Class -

Code:

---

function checkCollisionWithEnemies(bullet:MovieClip)
                  {
                        var block:Block = new Block();
                        block.x = enemy.x;
                              block.y = enemy.y;
                        {
                  if (enemy.meter.width < 1)
                        {
                                enemy.stop();
                                swapProperies(enemy,block);
                                removeChild(enemy);
                                enemy = null;
                                addChild(block);
                                }                 
                    function checkCollisionWithPlayer(block:MovieClip)
                          {
                                if (player!= null)
                                {
                                        Collision.block(block, player);
                                        }

---

I'm using the Collision.block(block, player) method call using the Collision class/doc, this works fine with collision between player and enemy, not why for this new object: block as shown below:

- Main Class -

Code:

---

function onEnterFrame(event:Event):void
                        {
                if (player.hitTestObject(enemy))
                  }
      Collision.block(player, enemy);
      }

---

The only difference is that it's within a different function of onEnterFrame instead of heckCollisionWithPlayer, surely that shouldn't make a difference?
Anyways any help or suggestions would be greatly appreciated.

Thanks

Jonesy