As far as I Can tell you only get one (the one being the blood dragon plate armor) of the promo DLC items with the steam version instead of all of them. Apparently you are supposed to get the key from the steam version and put it in EA's origin launcher to link the game and get the promotional items, but that is no longer possible because Steam
While it's great to enjoy the best of Dragon Age's combat and storytelling in more compact form, it's an unsatisfying meal for the money. But here's the thing with Dragon Age DLC - you get dessertThe problem here is that Steam and EA had a fallout, related to distribution of Dragon Age II DLCs. EA pulled DA II from Steam after that. They later closed Bioware Social site (which they bought) and shut down services. Steam is working with license they have.
What you do with alistair affect his cameo in DA2. Siding with behlen/harrowmont also gives you a side quest in DA2, lelianna and zevran can also make an appearance too, and yuo get extra dialogue between isabela/zevran or isabela/alistair dependng what happens at the pearl