The origins seem to translate directly over with little to no updates (other then recalculating wounds) and by comparison, DH careers have 3-4 less starting skills/talents, but if we were to create a "random talent/skill chart" and a "random number of random talent/skill chart" similar to 1E of WFRP it seems easy enough to port over these careers.
We could make these charts divided by origin and career, with a certain number of them rolling on the career talent/skill chart and one or two on the origin skill/talent chart.
As for the backgrounds from The Inquisitor's Handbok and Disciples of the Dark Gods, I think a few fit in as birthright (for example, I would put Untouchable as a birthright) while others (tranch war veteran) would be under trials and trevails.
Two other questions come to mind. 1) How to adapt alternate career ranks to Rogue Trader and 2) other then then "rogue" in the Rogue Trader career, where is the Rogue Trader RPG scoundrel, rogue, thief character at?
Most of the origins from DH easily fit over or in the same step/slot with ones already presented in Rogue Trader. Scholar Progenium fits over Imperial World (IMHO) while Feral World filts over Death World. Mind Cleanse is a bit more difficult but could be placed over Void Born or adapted as a Birthright option.