Awesome, Dear Boy: Angelina Jolie agreed to do the first film because of all the locations she would get to visit. She fell in love with Cambodia, leading her to move there and help with a minefield cleanup. It was also where she met and eventually adopted her first son, Maddox.
Executive Meddling: Surprisingly, with music in first film. They changed two different musicians and in the end picked up Graeme Revell, giving him 10 days for going to London from Australia, writing whole OST from nothing, blending it with already picked songs, orchestrating it and adding to film right before the premiere. This ended with really rushed production and many similarities with his previous work, Pitch Black.
Later, Revell excused for what even he considered poor work and remastered whole track, adding 3 new pieces (with much better, but unused main theme).
First film was advertised under U2's Elevation, so no one really bothered that there was no OST till last days before release.