rp4wp-custom-loop-single.php

<?php
/**
* Setup some data
*/
// get the post type
$post_type = get_post_type( get_the_id() );
// The settings object
$pt_settings = RP4WP()->settings[ 'general_' . $post_type ];

/**
* Get the children
*/
$plm = new RP4WP_Post_Link_Manager();
$children = $plm->get_children( get_the_id() );

/**
* @todo count amount of $children and fill up with manually set or random posts of current category
*/ 

/**
* loop and display
*/
if ( count( $children ) > 0 ) {
  
  // Manager Template
  $manager_template = new RP4WP_Manager_Template();
  
  // Load the template output
  $manager_template->get_template( $template, array(
    'related_posts'  => $children,
    'heading_text'   => $pt_settings->get_option( 'heading_text' ),
    'excerpt_length' => $pt_settings->get_option( 'excerpt_length' ),
    'post_type'      => $post_type
  ) );
  
}