To check, you can simply use the Russian alphabet string to check that all characters work without problems:
абвгдеёжзийклмнопрстуфхцчшщъыьэюя
АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ
I have a same problem with Soundshow interface,Chinese (Traditional Chinese) characters are displayed as squares in the lastest version too,so i hope the new version in the future can support Chinese (Traditional Chinese) to show or adding function to change font for some specific characters.thank you.