Robert Pattinson took a boat driving lesson so he would be able to drive the boat in the honeymoon scenes. Despite taking lessons, he crashed the boat in both the lessons and while filming in Brazil.
The sex scene between Edward and Bella originally caused the film to receive an R rating by the MPAA. The scene had to be reshot and edited to receive a PG-13 rating. According to interviews, Robert Pattinson and director Bill Condon blamed Kristen Stewart's wild "thrusting" during filming. Condon said, "Well, I think that's true. [Kristen] got very into it. I hate to be clinical, but [there are] guidelines on thrusting intercourse. Not to make people too excited, it was never explicit, but I think any movement that suggests that it is is what [the MPAA] object to."
The wedding scene in Part 1 was the last scene the cast and crew shot. It was also shot under tight security. A helicopter hovered above the set, off-duty police officers surrounded the location, and sheets and umbrellas were used to protect the set from aerial shots being taken.
There are over 1400 special effects shots in the film. Most of which were used on Kristen Stewart to achieve Bella's pregnancy appearance.
Kristen Stewart said in an interview that filming Bella and Edward's honeymoon sex scene was hard to do, but she was very happy with the final result.
Stephenie Meyer: (at around 13 mins) She can be seen as one of the wedding guests as Bella walks down the aisle.