The Time of Angels (1) - S5-E4
Continuity mistake: When the Doctor is ready to catch River Song, the TARDIS exterior shown is that of the Tenth Doctor's, not Eleven's. In particular, the St John's Ambulance logo is missing. (00:04:35)
The Time of Angels (1) - S5-E4
Continuity mistake: When River shows Amy and the Doctor the video of the Angel, next to the Doctor on the ceiling is a bar with two cloth handles, one on each end. The Doctor accidentally rips off the handle closest to him and the viewscreen. A minute later when Amy is alone and we are looking at the Angel video, this handle is back up. It's gone again in subsequent shots.
The Time of Angels (1) - S5-E4
Continuity mistake: When the Doctor is looking through a hole in one of the pages in the book on the Weeping Angels and River is asking him how early in his timeline this is, which of his hands is on the page changes between shots. (00:17:26)
The Time of Angels (1) - S5-E4
Continuity mistake: When Alistair confronts River, the two guards with him stop and point their guns at her as he walks forward, changing position between the wide shot and the following close-up of Alistair. (00:03:05)
The Time of Angels (1) - S5-E4
Continuity mistake: River's position when she turns away from the door changes between the security playback the Doctor and Amy are watching and the footage shot actually on the ship. (00:03:30)
The Time of Angels (1) - S5-E4
Continuity mistake: When the Doctor leans on the glass case with the home box, he clasps his hands together. In the next, wide, shot, his hands are separated and in loose fists. (00:01:48)
The Time of Angels (1) - S5-E4
Continuity mistake: When the Doctor and Amy are in the museum looking at the Home Box, after they steal it, they run to and enter the TARDIS, which is parked at the end of the hall by the last glass case. However, in the first shots of them in the museum, the camera was pointed directly at that spot, and the TARDIS wasn't there. (00:01:30 - 00:02:00)
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.