Does it work with the default WP theme because I don’t see the default theme in the list of themes on your site? Have you contacted the plugin author first to solve the problem? What errors related to our theme did plugin author provide?
Yes, I found that you used the very old version of the Royal theme and included plugins and updated theme to avoid problems from your side. You can update theme from version 4.7.2 to 4.7.3 using autoupdate option (Dashbaord > Updates). 4.7.3 was minor update that includes fix of the one woocommerce file that’s why we make it available for the autoupdate only.
If you use FTP methor to update theme then you can copy theme folder from the updated site and update the other sites using this copy.