HM CMB: Post Select Field for CPT ID

Unfortunately it is not possible to modify the field to use the name instead of ID and to keep the AJAX functionality.

You could use a standard select field, and pass the post data in the desired format to this – although you will loose the AJAX functionality.

The only way to achieve 100% of what you want is to create a custom CMB Field Type.

Unfortunately the Post_Select_Field and Select_Field classes are not the easiest to work with – the AJAX stuff in particular. I am currently working on a major overhaul of this and it should all be a bit clearer once this is released. Likeley to be a couple of weeks at least.

Update to include some code

This is how you would do it with a standard select field:

add_filter( 'cmb_meta_boxes', 'cmb_sample_metaboxes' );
function cmb_sample_metaboxes( array $meta_boxes ) {

    $post_select_options = array();

    $my_query = new WP_Query( 'post_type=post&posts_per_page=100' );

    while ( $my_query->have_posts() ) {
        $my_query->the_post();
        global $post;
        $post_select_options[$post->post_name] = get_the_title( get_the_id() );
    }

    wp_reset_postdata();

    $meta_boxes[] = array(
        'title' => 'CMB Test - all fields',
        'pages' => 'post',
        'fields' => array(
            array( 'id' => 'field-ID', 'name' => 'Post Select field', 'type' => 'select', 'options' => $post_select_options, 'allow_none' => true ),        
        )
    );

    return $meta_boxes;

}