Responsive, image viewer only, in random order

Hi there

I am using NextGEN Plus and wish to display a set of thumbnails in a random order, but without the slideshow feature.

I’m currently using the shortcode below but the random functionality doesn’t work.

What do I need to correct this as well as disable the slideshow so that it is just a single image browser.

[ngg_images gallery_ids="2" display_type="photocrati-nextgen_pro_thumbnail_grid" source="random"]

many thanks

https://www.ads-software.com/plugins/nextgen-gallery/