wp-mcm category shortcode not working

Hi
I can’t get [wp-mcm category="<slug>"] working on either pages or posts. It’s just writing out the text e.g [wp-mcm category="peru"].

I am using WP in a Magento template via Fishpig’s integration extension. Is that likely to cause conflict?
WP 4.1.10 MagentoCE 1.8.1

Kind regards
J

https://wordpress.org/plugins/wp-media-category-management/