...but I'm assuming they only send them within Germany, and I live in Slovakia.
The question is: where can I book the SparNight ticket from Bratislava to Berlin if I am not living in Germany?
I get a Bratislava-Breclav ticket, let's say, for a regular carriage with seat compartments.
Get on Metropol in Bratislava, get off in Breclav. Find the carriage with the bed sleeper indicated on my Hohenau-Berlin ticket. Get on and sleep. :-) Does that sound right?
... is it completely okay and legal to get on the train in Breclav even though the ticket is from Hohenau?
I heard from a friend that tickets for overnight friends can be purchased directly from the conductor at the station if there are free spaces left - if I don't get on in Hohenau, the conductor will not sell my spot to someone else, thinking I have missed the train, right?