Update:
Ok thanks to
Amet I finally have this figured out. It's not a completely satisfying solution, but it's better than nothing.
Here is the solution step by step to make Cyrillic subtitles display correctly:
1. First create the folder in which we will place the cyrillic supporting font. Use this guide (I've tested it on windows only):
OS X
~/Library/Application Support/Kodi/Media/Fonts (If the fonts folder doesn't exist create it)
Android
Android/data/org.xbmc.kodi/files/.kodi/Fonts/ (If the fonts folder doesn't exist create it)
Windows
Start - type %APPDATA%\kodi\media\Fonts - press Enter (If the fonts folder doesn't exist create it)
Linux
~/.kodi/Fonts (If the fonts folder doesn't exist create it)
OpenElec
/storage/.kodi/Fonts (If the fonts folder doesn't exist create it)
2. Next you need to get a font with Cyrillic support in it. I repeat not a Cyrillic font but one with cyrillic support in it (like the kind you write with in Word when you switch the language button in the windows taskbar). You can search for one online, or if on windows you can navigate to the Windows Fonts folder (C:\Windows\Fonts) and there I recommend taking
Arial Unicode MS Regular, just copy it and paste it into Kodi's Fonts folder. It will its display filename as
ARIALUNI.TTF and that's how you'll see it in Kodi's settings menu.
3. Open Kodi and go to: System > Video > Subtitles > Character Set
There choose Cyrillic Windows. While you're there go to
Font to use for text subtitles and change the font to
ARIALUNI.TTF using the arrows on the right.
Finally close and restart Kodi and the next time you play a movie your Cyrillic subtitles should playback correctly.
The downside is that other latin based eastern european font characters won't so you have to change back to Central European (Windows). It's a bummer but for now at least it works somehow.
