The current version is 2.01, but you still didn’t correct the language file names.
In WP-Advanced-Search.php you have:
load_plugin_textdomain('WP-Advanced-Search', false, dirname(plugin_basename( __FILE__ )).'/lang/');
The files in lang folder must have the name like is defined in the code above: WP-Advanced-Search-xx_XX.mo and WP-Advanced-Search-xx_XX.po, wih upper case at beginning.