Group not working properly

I created a group using MB Builder and set it to:

• collapsible true
• default_state collapsed

and added some fields with default values and conditional logic.
NOTE: my fields work perfectly when not in group

The result is:

• The group is not collapsed
• There is no visual indication that there is a group at all
• The fields are just displayed as if they are not in a group
• Default values of fields are not set (aka lost)

Is there a bug or limitations with the group extension?

the code:

<?php

add_filter( 'rwmb_meta_boxes', 'mytheme_register_meta_boxes' );
function mytheme_register_meta_boxes( $meta_boxes ) {

    $meta_boxes[] = array (
        'title' => 'Category custom options',
        'id' => 'dmb-cat-single-options',
        'fields' => array(
            array (
                'id' => 'dmb_cat_group_top_page_content',
                'type' => 'group',
                'name' => 'Top page content',
                'fields' => array(
                    // MAIN MENU
                    array(
                        'type' => 'heading',
                        'name' => 'Main menu',
                    ),

                    // [select] Show main menu yes no
                    array (
                        'id' => 'dmb_cat_main_menu_yesno',
                        'name' => 'Show main menu?',
                        'type' => 'select_advanced',
                        'placeholder' => 'Select an Item',
                        'options' => array(
                            'yes' => 'Yes',
                            'no' => 'No',
                        ),
                        'std' => 'yes', 
                    ),
                    // [select] Custom main menu
                    array (
                        'id' => 'dmb_cat_main_menu_custom_yesno',
                        'name' => 'Change default main menu?',
                        'type' => 'select_advanced',
                        'placeholder' => 'Choose',
                        'options' => array(
                            'yes' => 'Yes',
                            'no' => 'No',
                        ),
                        'std' => 'no', 
                        'hidden' => array( 'dmb_cat_main_menu_yesno', '=', 'no' ),
                    ),
                    // [select] Main menu - menu select
                    array (
                        'id' => 'dmb_cat_main_menu_select',
                        'name' => 'Select main menu',
                        'type' => 'select_advanced',
                        'placeholder' => 'Select a menu',
                        'options' => array(
                            'main' => 'Main menu',
                            'footer' => 'Footer menu',
                        ),
                        'visible' => array(
                            array( 'dmb_cat_main_menu_yesno', '=', 'yes' ),
                            array( 'dmb_cat_main_menu_custom_yesno', '=', 'yes' )
                        ),
                    ),

                ),
                'default_state' => 'collapsed',
                'collapsible' => true,
                'group_title' => 'Top page content',
            ),
        ),
        'taxonomies' => array(
            0 => 'category',
        ),
    );
    return $meta_boxes;

}