Using a RenderTickHandler makes the game lag, not even opening the save

I'm having problems with Rendering a Wavefront Object as Armor.

So, I've been looking around 'da webs' and didn't find anything usefull. I tried using the 'getArmorModel' method in the ItemArmor class (overriding it in my Item class), but it doesn't get called. Do I need to make anything else so it does get called?

As that didn't work I tried to setup a RenderTickHandler, however, now the game runs really slowly, and fails to open the world, because of that slowness.

I'm using TickEvents.RenderTickEvent, and I've tried  registering my handler in both FMLCommonHandler and MinecraftForge.EVENT_BUS. here is my code:

RenderTickHandler:

public class RenderTickHandler{

/*public RenderTickHandler(){ }*/

HashMap<EntityPlayer, ItemStack> map = new HashMap();

public void addArmorToList(EntityPlayer player, ItemStack stack){

	if(map.get(player) != null)
		map.put(player, stack);
}

@SubscribeEvent
public void onPlayerRender(/*RenderPlayerEvent*/ TickEvent.RenderTickEvent event){

	EntityPlayer player = Minecraft.getMinecraft().thePlayer;
	ItemStack stack = map.get(player);

	if(stack != null){
		if(stack.getItem() instanceof WuellrovKnightArmor){

			WuellrovKnightArnorRender.render(player, ((ItemArmor) stack.getItem()).armorType);

		}


	}
}
}

ClientProxy:

	public static RenderTickHandler renderer;

@Override
public void initRenderes() {

	renderer = new RenderTickHandler();
	//FMLCommonHandler.instance().bus().register(renderer);
	MinecraftForge.EVENT_BUS.register(renderer);
}
}

Additionally, I'm running the game on debug mode, in eclipse, which ran just fine using the RenderPlayerEvent, however it didn't get called (that might be why... </sarcasm>), and other models work just fine.