Does not work on featured images in Sensei courses?

Hi,

I have this plugin installed in a site where I use the Sensei plugin of Woothemes. It can be very time consuming to add a feature image lesson per lesson, so I was very glad when I found your plugin.

However, although I checked the lessons and courses in your plugin settings to enable it even there, it does not seem to work on the courses and lessons.

It does work on normal blog posts and Woocommerce products though.
Am I doing something wrong? It looks like it recognizes the Sensei courses and lessons because it is available to check and enable it in your plugins settings. How come the featured image option does not show up in the courses and lessons listings I wonder?

Thanks,
Annie

https://wordpress.org/plugins/wen-featured-image/