Thirdfloor Fellowship should not read this!
Short version: I Replaced Nyarlahotep with Stepehn Alziz, the Kchtoma with Delta Green, and the Twilight Queen becomes an avator of Shub-Niggurath.
The Tribunal are products of a joint effort between Shkryth and Karotechia. Nazi Clone assassins with South Afrikan accents. Weee!
Basically I started the Pc's as 'civillians' in a joint DEA, FBI, ATF taskforce tracking the appearance of a new hallucinagenic "Pixie" dust. I morphed the Pixie dust from Nocturnum's Twilight Queen Adventure with the DG book Countdown's T'Cho T'cho cartel. The Twilight Queen becomes an avatar of Shub-Niggurath.
I play the Pc's as pawns caught in a greater war between the Shyk'ryth and Shub-Niggurath. Nyarlahotep, as DG's Stephen Alziz assists, thwarts, and generally keeps the pc's on their toes. He provides information for a price...
At the end of that scenario all surviving pc's have had a slight taste of the mythos, they all have the mark of the twilight queen (so far company dermatologist's haven't been able to explain the matching melanin clusters on each agents forarm), and all have experience in filing 'creative' field reports. This gets them noticed by DG.
I used a scenario called Flight 714 from the original Brp version of Nocturnum. A nice tie in to get them on the trail of Timothy Ekloff. In the morphed version he is still former CIA, but he also was a Green Beret back in the Nam and has ties to the T'cho T'cho. Mixed loyalties can be fun!
At the end of this adventure each gets at telephone call asking them to attend a night at the opera. They are indoctrinated into DG, which provides support for the times later in the Nocturnum game when they are supposed to be on the run. (Karotechia/Tribunal did a frame up of them)
I mixed in some 'filler' scenarios to stitch together the threads.
Overall I used the following Scenarios from Nocturnum:
Maddness of Twilight queen, Visiting hours, wanted (kitbashed version), A family affair, Visiting hours, Thor's Anvil (you cannot let them miss a fight on an oil rig, The Weaving of three, Into the east, the Tyrr Nemaii, and Armageddon plain.
This probably doesn't make sense, but overall Nocturnum provided a nice guideline and story arch, whereas DG provided a bit more gritty detail.
Hope this helps.