The mod not only alters the existing game setting and factions, it also introduces new features not present in the base game and allows for some amusing changes to the way things fell out in the books, as this report on a campaign indicates:
"An interesting development in my campaign if anyone's interested. Managed to squash Robert's Rebellion after ol' King Aerys met an "unfortunate" end and Rhaegar ascended to the throne. Spared Robert's life which eventually led to him choosing trial by combat. He killed Rhaegar so now I'm playing as Aegon with Varys as my regent. Gotta say, this mod is leaps and bounds ahead of vanilla CK2 and the official ASOIAF games as well."