The Impossible Astronaut - S6-E2
Continuity mistake: When the alien kills Joy in the bathroom in front of Amy, the fragments of her body disappear from the floor once the alien approaches Amy. (00:28:28)
The Impossible Astronaut - S6-E2
Continuity mistake: When the Doctor is shot and killed while trying to regenerate on the beach, he falls with both legs extended. When River, Amy and Rory run up to him his left leg is bent. The camera cuts away again, and when it cuts back to show the Doctor's body one more time both legs are straight again. In addition, his left arm changes position between shots, between stretched out pointing away from his body on close-ups to bent with his hand resting on his thigh in wider shots. (00:08:15)
The Impossible Astronaut - S6-E2
Continuity mistake: When the Doctor goes to take off the spacesuit helmet, his hands change position between shots. (00:32:53)
The Impossible Astronaut - S6-E2
Continuity mistake: When the Doctor asks Rory if everyone's cross with him for some reason, his left arm moves from by his side in a close-up shot of him to stretched out to the console in a shot from behind. (00:15:06)
The Impossible Astronaut - S6-E2
Continuity mistake: When the school bus pulls up to drop Amy and Rory off in Monument Valley, there are no other vehicles in the area. When the bus pulls away, the Doctor has suddenly appeared with a vintage station wagon, parked by the side of the road where it should have been perfectly visible. And he was sitting on the hood, implying he'd been waiting there for a bit. (00:02:45)
The Impossible Astronaut - S6-E2
Continuity mistake: When the Doctor starts walking over to the lakeshore after the astronaut appears, he's still holding the wine bottle in his right hand. In the next shot where we can see his hand, the bottle is gone, without him having stopped to put it down. (00:06:34)
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.