Heart of Nightmare [Bonus Mission]

I installed the map using that clever method, the link to which is in the first post. I placed it inside the licensed game folder, and it displays and works perfectly fine. HOWEVER, instead of Svetlana, I get the hero Vyacheslav... and it's hilarious and frustrating at the same time when I try to complete the Necropolis mission with a hero who doesn't have any dark magic skills. This annoying thing keeps rebuilding the Fortress of Sanctuary into a Fortress of Light instead of the required Necropolis, and so on. What can I do? Is there a way to fix this?