Question False character encoding in one entire Windows application

Jul 20, 2020
So, today I've downloaded the text-to-speech Software UkrVox ( ), which is entirely in Ukrainian, so it's mostly Standard Cyrillic characters with a few less common Cyrillic ones and the same number symbols as in English. Unfortunately, the software, including the installer, interprets all of the Cyrillic text (numbers and Latin characters work fine) either as random characters or question marks. It looks like this:

The menus opened by the buttons also look like that:

One of the other buttons opens an .rtf help file, which contains an image showing me what the above menu should actually look like:

None of it says anything about character encoding. Does anyone have an idea how I can fix this? How can I start software and tell Windows to interpret it as Unicode, ANSI, etc. text?

I am using Windows 10 (version 1903) in US English on a 2-year-old HP 255 G6 laptop.
Control Panel -> Region -> Administrative, then "Change System Locale". Choose "Urkanian", "Russian" etc. Reboot.

I don't think "Ukranian Language Pack" will help - it will switch Windows to Ukrainian, but probably won't change code page for non-Unicode apps.