In the opening scene, Herr Schuler's wedding ring switches from his right hand to his left, then back onto his right again. Germans wear their wedding rings on their right hand.
In the scene at Lydia's house, the nanny is playing with Lydia's daughter who is walking around in bare feet. When Lydia arrives at home and the daughter jumps into her arms the daughter is now wearing slippers. Later in the same scene she's back to being in bare feet.
Mike meets Lydia in a cafe/restaurant. At the end of the meeting he throws a bill on the table. The folded/creased bill lands on edge. It stands upright. Change camera shot. A crumpled bill is lying flat on the table.
When Mike is being interviewed by the DEA, he places his hands on the table to challenge them to arrest him by handcuffing him.
The distance between his hands changes as the camera angles changing.
The distance between his hands changes as the camera angles changing.
In the opening scene when Schuler is taste testing the dipping sauces, he is getting some sauce accumulation on his fingers. Yet when his assistant informs him that the police want to talk with him, his fingers are clean.
Standard automatic external defibrillators do not allow the manual administration of a shock: they must first analyze the patient's heart rhythm - a tough thing to do when one of the electrodes is in your mouth - to determine what type of shock, if any, is required. Therefore, successfully using an AED to commit suicide, especially the way shown in this episode, would be a matter of extreme luck. (By the same token, don't try it as a party trick.)
In the opening scene, every one of the supposedly German characters speaks German with a noticeable accent. While the German lines are correct in form and content, the pronunciation is often off.
The German police officers were uniforms with just the word "Polizei" on them. Since the police in Germany is organised per state, the uniforms should have the coat of arms of the state the officers are from.
Walter and Jesse are looking for the cigarette that conceals a vial with the poisonous ricin. We see a Roomba robotic vacuum cleaner at work. Jesse empties the container and finds the undamaged cigarette amidst the dust. A Roomba cannot "swallow" an item like the cigarette with the vial. However, the whole point of the scene is that Walt has clearly placed the cigarette inside of the Roomba in order to deceive Jesse.
The defibrillator has German markings on it. However, the markings are grammatically incorrect since they were translated literally from English to German.
The bathroom where Schuler commits suicide is supposed to be in Germany. Yet the light switch and wall sockets are distinctly US, which look very different from the ones commonly used in Germany.