Hello,
system cfg cannot be opened with a notepad.
The problem that your game does not save the settings is "read only" on the files. Right click on the game folder -> properties, then remove read only and apply the changes to the folder and inner files and folders.
For security, repeat this separately for the system.cfg and SystemOptionGraphics.cfg files.
Unfortunately, the names of the voices are displayed this way. We will work on it.
However, you can still use the listen button to preview the voice and choose the one that you like.