Should I create one plugin for one button for WP ckeditor?

I created a single plugin for single button, I see it in wp admin panel but when I activate it the whole ckeditor dissapears((( Here is the plugin.js

/*
Copyright (c) 2003-2010, CKSource - Frederico Knabben. All rights reserved.
For licensing, see LICENSE.html or http://ckeditor.com/license
*/


( function() {
  CKEDITOR.plugins.add( 'mypluginru',
  {
	
	init: function( editor ){
		
		editor.addCommand( 'insertRU',
			{
				
				exec : function( editor )
				{    
										
					editor.insertHtml( '[lang_ru]' );
				}
			});
		
editor.ui.addButton( 'RU',
		{
			
			label: 'Insert RU',
			command: 'insertRU',
		    icon: this.path + 'plugin.png'
		 } );
	}
} );
} )();

Here is myplugin.php

<?php
/*
Plugin Name: mypluginru
Description: RU button to CKEditor 
Version: 1.0
Author: annaweb
Author URI: http://annaweb.msk.ru/
*/

require_once 'mypluginru_class.php';
add_filter( 'ckeditor_external_plugins', array(&$mypluginru, 'ckeditor_plugin') );
add_filter( 'ckeditor_buttons', array(&$mypluginru, 'ckeditor_buttons') );
?>

Here is mypluginru_class.php

<?php
class mypluginru {
	var $version = '1.0';
	var $plugin_path ="";

	function mypluginru()
	{
		$this->__construct();
	}

	function __construct()
	{
		$siteurl = trailingslashit(get_option('siteurl'));
		$this->plugin_path = $siteurl .'wp-content/plugins/' . basename(dirname(__FILE__)) .'/';
	}

	function ckeditor_plugin($plugins) {
		$plugins['mypluginru']=$this->plugin_path.'ckeplugin/';
		return $plugins;
	}

	function ckeditor_buttons($buttons) {
		$buttons[]=array('RU');
		return $buttons;
	}
}

$mypluginru = new mypluginru();
?>

Excuse me for such a long post. Maybe someone will help!

Well, I've done! The image must be GIF not PNG. And the editor itsef loads very very slow...