This is the functions.php from the plugin that creates the CPT and the metaboxes
<?php

/*
Plugin Name: Scrutinies Functions
*/

add_action( 'init', 'register_cpt_artist' );

function register_cpt_artist() {

    $labels = array(
        'name' => _x( 'Artists', 'artist' ),
        'singular_name' => _x( 'Artist', 'artist' ),
        'add_new' => _x( 'Add New', 'artist' ),
        'add_new_item' => _x( 'Add New Artist', 'artist' ),
        'edit_item' => _x( 'Edit Artist', 'artist' ),
        'new_item' => _x( 'New Artist', 'artist' ),
        'view_item' => _x( 'View Artist', 'artist' ),
        'search_items' => _x( 'Search Artists', 'artist' ),
        'not_found' => _x( 'No artists found', 'artist' ),
        'not_found_in_trash' => _x( 'No artists found in Trash', 'artist' ),
        'parent_item_colon' => _x( 'Parent Artist:', 'artist' ),
        'menu_name' => _x( 'Artists', 'artist' ),
    );

    $args = array(
        'labels' => $labels,
        'hierarchical' => false,
        'description' => 'Interviews with Catholic artists.',
        'supports' => array( 'title', 'editor', 'excerpt', 'thumbnail', 'trackbacks', 'custom-fields', 'comments' ),
        'taxonomies' => array( 'category', 'specialty' ),
        'public' => true,
        'show_ui' => true,
        'show_in_menu' => true,
        'show_in_nav_menus' => true,
        'publicly_queryable' => true,
        'exclude_from_search' => false,
        'has_archive' => true,
        'query_var' => true,
        'can_export' => true,
        'rewrite' => true,
        'capability_type' => 'post'
    );

    register_post_type( 'artist', $args );
}

function be_sample_metaboxes( $meta_boxes ) {
    $prefix = '_cmb_ds_';
    $meta_boxes[] = array(
        'id' => 'test_metabox',
        'title' => 'Test Metabox',
        'pages' => array('artist'), // post type
        'context' => 'normal',
        'priority' => 'high',
        'show_names' => true, // Show field names on the left
        'fields' => array(
            array(
                'name' => 'Test Text',
                'desc' => 'Dummy text to see what happens',
                'id' => $prefix . 'test_text',
                'type' => 'text'
            ),
        ),
    );

    return $meta_boxes;
}
add_filter( 'cmb_meta_boxes', 'be_sample_metaboxes' );

// Initialize the metabox class
add_action( 'init', 'be_initialize_cmb_meta_boxes', 9999 );
function be_initialize_cmb_meta_boxes() {
    if ( !class_exists( 'cmb_Meta_Box' ) ) {
        require_once( 'lib/metabox/init.php' );
    }
}

This is the single-artist.php code:
<?php
/*
 * Template Name: Artist
 * This template displays Artist Details
 */

remove_action('genesis_after_post_content', 'genesis_post_meta'); //remove post-meta
remove_action('genesis_before_post_content', 'genesis_post_info'); //remove post-info
add_action('genesis_after_post_content', 'child_get_artists_field'); //display meta-box content after the content

//Function to show the content
function child_get_artists_field() {
        echo '<strong>Bacon '. genesis_get_custom_field( '_cmb_ds_test_text' ) .'</strong>';
}

genesis(); // requires Genesis 1.3+
?>