Integración Master Slider con CMB2
$cmb_select_slider->add_field( array(
'name' => 'Elija el slider para Móvil',
'id' => $prefix . 'mobile_metabox',
'type' => 'select',
'show_option_none' => true,
'default' => 'custom',
'options_cb' => 'get_masterslider_names', //aqui esta la magia
));
<?php
$slider = get_post_meta(get_the_ID(), 'kiaplazasite_mobile_metabox' , true);
?>
<?php echo do_shortcode( '[masterslider id="' . $slider . '"]' );?>