If you don’t want to display the uploaded image in the lightbox, you can go to Reviews > Settings > Review Extensions > Tick the option Disable Lightbox and save.
The popup could be initialized by a third-party plugin or theme on your site. You can try to deactivate all plugins except CusRev, WooCommerce and switch to a WordPress theme then check the issue again.
We haven’t heard from you for more than two weeks. For this reason, I’ll assume that either you are not interested in this question/problem anymore or it has been resolved. If you still require any help, please start a new forum topic.