Subscriber to post a Custom Post Type

I am trying to setup a custom post type that will allow subscribers to submit a “extension” and that is it. The problem is when capabilities are setup like this the subscriber can select other posts to edit:

'edit_post' => 'read',
'edit_posts' => 'read',

If the capabilities are setup like this the subscriber can’t select any:

'edit_post' => 'edit_post',
'edit_posts' => 'read',

And finally, if the capabilities are setup like this the subscriber can not view the index table for the custom post type:

'edit_post' => 'read',
'edit_posts' => 'edit_posts',

Either I need a way to setup the capabilities so that the subscriber can view the index and edit only their own post or a way to filter the title edit options on the index page. Can anyone help?

/*
Plugin Name: WPDI Command Center
Plugin URI:
Description:
Author: Lucas Keiser
Version: 0.1-beta
Author URI: https://www.keisermedia.com/

    Copyright 2010  Lucas Keiser  (email : [email protected])

*/

class WPDI_Command_Center{

	function __construct(){
		add_action('init', array(&$this, 'extension_register'));
		add_action('admin_init', array(&$this, 'admin_init'));
		add_action('manage_edit-extension_columns', array(&$this, 'extension_edit_columns'));
		add_action('manage_posts_custom_column', array(&$this, 'extension_custom_columns'));

		$current_page = substr(strrchr($_SERVER['PHP_SELF'], '/'), 1, -4);
		if( $current_page == 'page' || $current_page == 'page-new' || $current_page == 'post' || $current_page == 'post-new' ){
			add_action('admin_head', array(&$this, 'add_post_enctype'));
		}

	}

	function extension_edit_columns($columns){
		$columns = array(
			'cb' => '<input type="checkbox" />',
			'id' => __('ID'),
			'title' => __('Extension Title', 'wpdi-cc'),
		);

		return $columns;
	}

	function extension_custom_columns($column){
		global $post;
		echo '<pre>';
		print $column;
		echo '</pre>';
		if( current_user_can('edit_extension', $post->ID) ){
			switch( $column ){
				case 'id':
					break;

				case 'title':
					break;
			}
		}
	}

	function add_post_enctype() {
		echo '
		<script type="text/javascript">
		jQuery(document).ready(function(){
			jQuery("#post").attr("enctype", "multipart/form-data");
			jQuery("#post").attr("encoding", "multipart/form-data");
		});
		</script>';
	}

	function extension_register(){
		global $wp_roles;

		$labels = array(
			'name' => _x('Extensions', 'post type general name'),
			'singular_name' => _x('Extension', 'post type singular name'),
			'add_new_item' => __('Add New Extension'),
			'edit_item' => __('Edit Extension'),
			'new_item' => __('New Extension'),
			'view_item' => __('View Extension'),
			'search_items' => __('Search Extensions'),
			'not_found' => __('No extensions found'),
			'not_found_in_trash' => __('No extensions foound in Trash'),

		);

		$args = array(
			'labels' => $labels,
			'public' => true,
			'publically_queryable' => true,
			'show_ui' => true,
			'capability_type' => 'post',
			'capabilities' => array(
				'edit_post' => 'read',
				'edit_posts' => 'read',
				'edit_others_posts' => 'edit_others_posts',
				'publish_posts' => 'publish_posts',
				'read_post' => 'read_post',
				'read_private_posts' => 'read_private_posts',
				'delete_post' => 'delete_post',
			),
			'query_var' => true,
			'rewrite' => true,
			'heirarcical' => false,
			'menu_position' => false,
			'supports' => array(
				'title',
			),
		);

		register_post_type('extension', $args);

	}

	function admin_init(){
		if( current_user_can('edit_others_posts') ){
			add_meta_box('extension_meta', 'Extension Information', array(&$this, 'extension_meta'), 'extension', 'normal', 'high');
		}
	}

	function extension_meta(){
		global $post;
		$custom = get_post_custom($post->ID);
		$download_url = ( isset($custom['download_url'][0]) ) ? $custom['download_url'][0] : 'https://';
		?>
        <p><?php _e('In order for our team to evaluate your extension, we must have access by either a direct download or through user submittion.', 'wpdi-cc'); ?></p>
        <p>
        	<strong><label><?php _e('Direct Download URL', 'wpdi-cc'); ?></label></strong><br />
        	<input type="text" id="download_url" name="download_url" class="code" style="width: 99%;" value="<?php echo $download_url; ?>" />
        </p>
        <?

	}

	function extension_save(){
		global $post;

		update_post_meta($post->ID, 'download_url', $_POST['download_url']);
	}

}

$wpdi = new WPDI_Command_Center();