Does CollisionGroup instantiation order matter?

[codevinsky]

Cross posted from here.
 
I've got a prefab class that inherits from Group.
 

var PipeGroup = function(game, x, y, collisionGroup, collidesWith) {Phaser.Group.call(this, game);var topPipe = this.create(0,0,'pipes');topPipe.physicsEnabled = true;topPipe.body.kinematic = true;topPipe.body.setRectangle();topPipe.body.setCollisionGroup(collisionGroup);topPipe.body.collides(collidesWith);this.x = x;this.y = y,}; PipeGroup.prototype = Object.create(Phaser.Group.prototype);PipeGroup.prototype.constructor = PipeGroup;

And in my main game's create function:
 

create = function() {  ..        this.playerCG = game.physics.createCollisionGroup();  this.pipeCG = game.physics.createCollisionGroup();   // add our player to the stage  this.player = this.add.sprite(game.world.width/3,220,'bird');   // enable physics on our player  this.player.physicsEnabled = true;    // add our player to the player collision group  this.player.body.setCollisionGroup(this.playerCG);  this.player.body.collides([this.pipeCG], this.death, this);  ..  game.time.events.loop(Phaser.Timer.SECOND,this.generatePipes, this);}

and generatePipes looks like:
 

generatePipes: function() {  var pipeY = game.rnd.integerInRange(-120,120);  var pipes = new PipeGroup(game,game.world.width + 32, pipeY, this.pipeCG, this.playerCG);  this.player.body.collides([this.pipeCG], this.death, this);}

However, the player is never colliding with the pipes.
 
Can you modify a collision group after the create phase of a state?

I'm a bit at a loss to figure out why this doesn't work.

[rich]

I'll post up examples of how to use this tomorrow, I've been refining the process today.

[codevinsky]

Just for my own sanity, is there anything I'm doing wrong? I've been banging my head against this for hours.