Artisteer 2.5 Index.php with WP Pagenavi

<?php
get_header();

 if (have_posts())
 {
    while (have_posts())
    {
      art_post();
    }
    /* Start add page navigation to index page */
    if(function_exists('wp_pagenavi') ) {
        wp_pagenavi();
    } else {
    art_page_navi();
    }
    /* End add page navigation to index page */
 } else {
    art_post_box(
        __('Not Found', 'kubrick'),
        '<p class="center">' .  __('Sorry, but you are looking for something that isn&#8217;t here.', 'kubrick') . '</p>'
        .  "\r\n" . art_get_search());
 }

get_footer();