RTF is a global modification that replaces all towns in the game.

Kirill is most likely dead, as Zana is once again serving Kha-Beleth, and Sarah has gone to the afterlife with him.
Railag and Tieru are searching for the dark messiah in the free cities, and they have most likely found him! Railag is fighting the undead somewhere in the streets of Stonehelm, while Tieru is waiting for Sareta together with Dilan in the Temple of Ilat (I have no other explanation for who that "ancient enemy of Kha-Beleth" is).
Murazel lives in Hammerfall and instructs the priests; perhaps, during the orcs' transition to the dark side, she will command the defense or die – I don't know.
Jorgen may switch to the side of the Elementals – then he will guide them on a journey through the Unicorn Empire, where mercenaries, dwarves, and Chimera mages have set up camps.
Duncan will stay in the capital until the dark dwarves and nagas knock on his door; when they do, they will go to Tarlad, where a war is raging between Letos and the order of paladins – and when everyone is destroyed, Wolfsten and Faidaen will come to the rescue (they are also suffering losses), and then the war will spread to Irollan and Grimheim.