Wrong codepage in popup-maker-AJAX-login-modals add-on

@gkovaleff – Can you email support directly for extension issues. We are not supposed to provide support for paid products here.

support at wppopupmaker.com

Happy to get this worked out for you. The translation is actually provided by WP core in that case. We duplicated their login form exactly for maximum compatibility with other plugins and themes. So the Register word should be replaceable via WP mo files.