Sage 9, Blade and Buddypress

sage
, ,
10

This seems to be the offending Memberpress function

  // Template selection
  public static function template_include($template) {
    global $post, $wp_query;

    if(!is_singular()) { return $template; }

    if(isset($post) && is_a($post, 'WP_Post') && $post->post_type == MeprProduct::$cpt) {
      $product = new MeprProduct($post->ID);
      $new_template = $product->get_page_template();
    }

    if(isset($new_template) && !empty($new_template)) { return $new_template; }

    return $template;
  }

Edit:
Actually I was able to get a Memberpress Registration page loading by slightly modifying the code @mecanographik wrote:

add_filter('template_include', function ($template) {

    global $post;

    if(isset($post) && is_a($post, 'WP_Post')) {

        $default_template = locate_template( array( 'template-custom.blade.php' ) );
        if ( '' != $default_template
            && '' == $post->page_template // Only when page_template is not set
        ){
            //return $default_template;
            $template = $default_template;
        }
    }

    return $template;
}, 99);