Welcome to MobileRead, cyberfly!
I'd say your first step is to re-flash with the base firmware and see if that fixes your 505's strange behavior. If it does, then you'll know the conflict is with the Russification process, and perhaps you can work out the difficulties from there.
I've not tried to Russify one, and I still use my 500 anyway, so I can't really offer any more specific insights, but I know there are other folks around the forum that can.