Thank you for your explanation.... Although I'm a Xerox's customer.....I don't really think I should report a problem to each manufacture individually since Xerox has sold me the machine with the EFI Ex-i Rip. I didn't buy the Rip separetely. It's their responsobility to contact with EFI developer Team fixing the issue. IMHO.
You realize EFI makes Fiery right?
This issue is just the EFI Fiery, even the keyboard is provided by EFI, which is why it doesn't match the keyboard in every app at the printer that isn't the Fiery app. Xerox keyboard also has multiple layouts you can choose while in it, which includes Russian.
In short, you need to report the issue to EFI, Xerox can't fix it , although you may be able to report the issue to Xerox Europe to forward to EFI if you have a maintenance agreement with them, but it can't be done on this peer-to-peer forum.
EFi may be able to help you on their forum though
There's another one bug I've found that prevents a non-English user to enter to the Fiery as an admin. I'm unable to enter admin's credentials since the Xerox's system has been set to the Russian language. There are just Russian letters and it's impossible to change language for example like in Windows OS by pressing Shift + Alt or in Android OS. A user is expected to change language in system and then enter to the Fiery.