Blocksy Shortcode

I use Blocksy 2 and the plugin ‘MB Custom Post Types & Custom Taxonomies.’ When I apply the shortcode [blocksy_posts post_type=”veranstaltung”], the posts are displayed. However, when I try to display specific post_ids using [blocksy_posts post_ids=”1028,984″], they are not shown. What am I doing wrong?

The page I need help with: [log in to see the link]