The first time we see the scene where Kyle surprises Laura by placing a necklace around her from behind, the song "Don't Say Goodnight" by David Roberts is heard playing in the ballroom. However, the second time we see the same scene towards the end of the film, "Time and Time Again" by Ian Thomas, the first song played by the DJ, is heard playing.
As 'Evan' is falling over the balcony, the actor playing him is seen standing to the left of the column while his stunt double is going over the railing.