From what I understand this musical takes many liberties as well. It's credited as being loosely based on the novel with the biggest change probably being the substitution of West Africa in place of the India setting in the novel.
I just finished listening to the entire album, and I must say that it's quite beautiful. Lippa's music is quite different than what I've heard from him before. Sierra sounds great - it's nice to hear her belting again. Julia Murney also sounds GREAT. I know not everyone likes her voice, but I am a fan. Overall, I was really pleased with listening to the show. It's be great to see it.