Interesting video by Deutsche Welle (DW) about do's and dont's when dining out in Germany.
https://p.dw.com/p/57lxN
Close to that topic is the DW video "How to fit in at a German dinner party"
https://p.dw.com/p/4shOj
Thread is open for posts with own views and experiences. I think that some things are missing or need to be clarified in detail but I will post it later on.