Continuity mistake: When the Doctor interrupts Mr. Copper's incredibly inaccurate description of Earth society to ask him where he got his information from, in a shot facing Mr. Copper, the Doctor's raised hand has only one finger extended. In the next shot, facing the Doctor, he has two fingers extended, with the other two only loosely curled. Shortly after this, the Doctor scratches his temple with that same hand, only for it to be absent in the next shot facing Mr. Copper. (00:11:40)
Continuity mistake: After Rickston asks the Doctor how "Mr. and Mrs. Fatso" (Morvin and Foon) are going to get through a narrow gap, when the Doctor responds that they're going to make the gap bigger, he passes Rickston a piece of metal. The steel bar's appearance changes between shots. (00:27:45)
Continuity mistake: When Mr. Copper is talking about how space-lane fraud could get him ten years in jail, the cut on his forehead changes sides, as does the panel behind him, revealing the shot to be flipped. (00:36:25)
Continuity mistake: After Morvin falls to his death in the engine, when Foon tearfully demands to the Doctor that he bring him back, and he tells her he can't, Foon's hand is gripping the railing in one shot with the two of them, but missing in a shot facing the Doctor as he says, "I know. I'm sorry." (00:37:45)
Continuity mistake: When Astrid tells Mr. Copper that she's going down to Deck 31 to find the Doctor, she's using her left hand to fit a teleport bracelet on her right wrist. In a shot facing Mr. Copper immediately after as he wishes her good luck, her left arm is suddenly by her side. (00:50:55)
Continuity mistake: The meteors are shown approaching and hitting the ship on the starboard (right) side. Twice, however, they are erroneously described as being to port (left): When the meteors are first seen on the scanner by Frame, and later when Frame tells the survivors in Kitchen 5 to go starboard because the port side of the ship is impassable.
Chosen answer: 1) When Stephen Moffat took over he ignored a lot of what had been developed before (there is not in-universe answer). 2) It would have killed Rose, so the Doctor absorbed the energy. His body regenerated before the energy could do a significant amount of damage that would prevent regeneration.