And how to I render the entityItems when I enter the world.
They now appear when I have right-clicked the container.
Client-server disparity. You don't have getDescriptionPacket implemented.
Assuming your TE is writing its inventory to its NBT (otherwise items would vanish on save/load), then this is all you need:
public Packet getDescriptionPacket() {
NBTTagCompound nbtTag = new NBTTagCompound();
this.writeToNBT(nbtTag);
return new Packet132TileEntityData(this.xCoord, this.yCoord, this.zCoord, 1, nbtTag);
}
public void onDataPacket(INetworkManager net, Packet132TileEntityData packet) {
readFromNBT(packet.data);
}