So, I recently bought Lure of the Expanse, not so much to play those adventures, but more as a sourcebook to get a really good idea at how to GM rogue trader. Since then I've been tempted to invest in Tattered Fates or Damned Cities. Are those books very compatible with RT?

Tattlered Fates is very RT compatible, as is the one in the back of Disiples of Dark Gods. Dammed Cities on the other hand is hard to fit into RT.

Depends. To use Damned Cities you have to have a reason for the RT to care. Perhaps he owns a shard of the mirror or a friend was killed while they were in port at Sinophia and then the story is personal. Perhaps a sub clause in their Charter calls for them to prevent the mirror from being reassembled and if that happens the Charter becomes null and void.

Mmmm... If you make your players to go through the House of ash and Dust (the adventure in the book of Disciples of the Dark Gods) and Tattered Fates, it wouldn't be so strange for the In quisition to "recruit" the RT in an informal way (a single inquisitor with some retinue, who would do "other things" in Dammed Cities... which also allows you to "save" the players if bad comes to worst).

from france

rt thing including lures of the expense can be integrating in dh. from my point of wiew rt is like a indefinte quaddis wating to be put under the rules of the imperium. beyond inquistion law but not beyond it s scrutinity.

so best way to play dh in rt or rt in dh is to says that bif i agents are here in under special condition to investigate. look a the eldar spirit stones. let say that in dh you find details seller and the name of the rogue trader or the planet source but you can't find the middle link beetwen them.

why wasting your time in the calisix sector? if you can't folows the chains from the small to the big folow it from the big to the small. soback to the special condition. of course showing up your badge office and scream unquisition is the last thing to do.

If you are looking at Tattered Fates and Damned Cities because Haarlock was a Rogue Trader, I wouldn't bother.

A. He's very unique, not like other Rogue Traders. Not much crossover.

B. There is *very* little information on Haarlock. Almost none. These DH adventures are about the acolytes hitting the side effects of Haarlock returning from who knows where. He's not in these adventures, and he's not directly trying to control minions against the acolytes. He probably doesn't know they exist. That will probably change in Dead Stars.

You might get more mileage out of Disciples of the Dark Gods and Creatures Anathama.

And, as someone else has posted, some of these books refer to the psychic powers that are in the DH core rulebook. I think you can extrapolate from context what they do, but if not, either replace them with RT psychic powers or get the core book.