Exclude skins from random skins

exclude_skins.php

add_filter('tc_skins_to_randomize', 'exclude_skins');
function exclude_skins( $_skins ){
  $_my_excluded = array(
    'grey.css',
    'grey2.css'
  );
  foreach ( $_my_excluded as $key )
    if ( array_key_exists( $key, $_skins ) )
      unset( $_skins[$key] );

  return $_skins;
}