Featured Category to Featured Slider

Hi, I would like to change featured category to featured tag. I tried to change featured.php file on line 10 from 'cat'=>ot_get_option('featured-category') to 'cat'=> ot_get_option('featured-tag') and theme-options.php on line 233 from 'id'=> 'featured-category', to 'id'=> 'featured-tag', and line 236 from 'type'=> 'category-select', to 'type'=> 'tag-select',
It looked ok, I can choose tag from menu. Homepage shows featured post by my choosed tag but also the newest posts so featured posts are mix of my choosed tag and newest posts. Can you help me solve this problem? THX ??