Hello,
Please, read our instructions how to translate theme very attentively https://www.8theme.com/demo/docs/royal/index.html#!/0_how_to_translate
To translate our theme strings you should translate default.po that is located in wp-content/themes/royal/languages folder using PoEdit. Then save it as described here http://betterwp.net/wordpress-tips/create-pot-file-using-poedit/ , it will create 2 files: .po and .mo, you need both to activate translation. At present in wp-content/themes/royal/languages folder I see only default theme file (untranslated) and de_DE.po file for WordPress 4.0 (untranslated too). de_DE.po won’t work, because our theme translation file and wordpress translation file are different things.
Regards,
Olga Barlow