Hey Filip,
I'm currently living in Bulgaria, that makes us neighbours
Anyway, making Cyrillic font would be very easy since 3DRad doesn't use .ttf, but a simple image with all the symbols... every character is just a 3D model of a square (2 polys), each mapped with the corresponding part of the image (see below)
You can simply copy the TextPrint folder, open the .DDS file with Photoshop (
here is the plugin). And draw your fonts, position them over the corresponding keys... and thats it.
Don't forget to add an alpha channel* to the saved .dds (see image above).
*- simply add another layer to the channels, control+click the layer with the fonts to select the outlines, then select the newly created alpha channel and control+i to invert from black (completely transparent) to white (completely opaque). Depending on your font size and detail you can either save with resolution of 512x512 or 1024x1024 pixels.
I hope that helps, the process is really easy and quick!