Skip-store-review-if-no-product-rating-in-review

class WCFM_Store_review_modifier {
    private $review_rating = null;
    public function __construct($comment_id) {
        $this->set_review_rating($comment_id);
        add_filter('wcfmmp_is_allow_product_review_sync_with_store_review', array(&$this, 'can_sync_with_store_review'));
    }
    public function set_review_rating($comment_id) {
        if ( get_option( 'woocommerce_enable_review_rating' ) == 'yes' ) {
            $this->review_rating = intval( get_comment_meta( $comment_id, 'rating', true ) );
        }
    }
    public function can_sync_with_store_review($is_allowed) {
        return $is_allowed && $this->review_rating;
    }
}

add_action('comment_post', function($comment_id) {
    new WCFM_Store_review_modifier($comment_id);
}, 49);