Continuity mistake: When Alex throws the useless GDR money from the rooftop Lara is sitting on the rim, wearing a red t-shirt. When Alex walks over to her and she gets up she's wearing the light-blue jacket she was sitting on. (01:07:35)
Continuity mistake: At the datscha the mother tells her kids how she lied to them about their father after he had left. She is rested on a reclining chair with a brown pillow. A second brown pillow appears and disappears in alternating shots. (01:29:40)
Answer: According to IMDb, Sigmund Jähn gave permission to be featured in the movie, but refused to play himself. It was very difficult to find an actor who looked like Jähn and spoke his typical dialect but after filming had begun, 'Wolfgang Becker' chose a Swiss actor. He was given complex make-up and was dubbed by another actor who came from Jähn's home region, the Vogtland.