Started off on Themeforest.
Me: ““Featured Image” has disappeared from products for me. Running just WP 4.1 and WooCommerce 2.3.7. Verified it’s the Royal theme by first deactivating all plugins, then switching to Twentyfifteen. Featured Image metabox returned once I swapped to Twentyfifteen.”
Helen: “Please, provide us the link to your site. Be sure you are using the last theme version.”
I’m on version 1.7.1. Verified again by installing a freshly-downloaded copy of Royal to a new WordPress installation with ONLY WooCommerce running. This is definitely an issue with the theme. Same issue as this person is experiencing (at the bottom): https://www.8theme.com/reply/49484/