Nice trip report
Just to update
ksguenov (and any future readers) - sadly there are no restaurant cars on any CityNightLine trains any more. However, in a sleeper, the attendant will still bring breakfast to your compartment in the morning. And in the evening, you can also buy drinks and light snacks from the attendant. Pax in couchettes or seats can also buy food from the attendant in the sleeper car. Or, of course, you can take your own food and drink onboard with you.