Read how to do it, solved all curses in kingdom management but it won´t give me to dialogue option about Vordakai when talking to Nyrissa at house at edge of time. :-/ Any idea why that might be?

I got the same issue. Did everything and didn't get the options for mentioning Armag, Tartuk, Vordakai, instead only got to mention Evindra. I figure the game bugged out because this was an evil playthrough. I got the Briar from the house and she accepted it, so clearly I was on the right track, however even though I had the detailed dialogue with Vordakai, Tartuk and Armag all, the options did not show up.

Ironically, I won the "secret ending" on my first playthrough almost 3 years ago, which was a goodie-two-shoes :) playthrough, and did so pretty much by default.

So I figure the proper flags get overwritten when speaking to Maegar-Vordakai in the throne room, or perhaps with Tartuccio after vassalizing him, although I think I spoke with Armag after all dialog with Maegar-Vordakai. I might try to unbug my game with a mod editing the flags, but the game itself really screwed up.