Hello,
As I see you have default po and mo files in the directory wp-content/themes/royal/languages, but you should create your own depending on the language you use.
Please read our documentation: https://www.8theme.com/demo/docs/royal/#!/how_to_translate
Also the problem of the blank page was related to Wishlist plugin. I’ve deactivated it. Please try to update it and check the site again having the plugin activated.
Thank you.
Regards,
Eva Kemp.