Movie Set artwork not shown

I'm having issues with movie sets and hopefully someone can lend me a hand.
I'm using the TinyMediaManager to create my NFO files and using Kodi v18 Leia along with the Artic Zephyr 2 skin.  I'm noticing that after working my movie files in TMM and then adding them to Kodi, the movie sets are indeed created, but the posters are not being added as selected in TMM, but rather a poster of one of the movies within the set shows up as the movie set poster. 
Anyway to get this done automatically instead of manually selecting the movie set poster/background art within Kodi?