Raye: In chapter 3, the Order of the Flaming Rose will react differently depending on the faction you chose as well. If you sided against them, stay well clear. :p
revial: Well, the guide may say to stay clear, but in reality all they do is talk dirty to you (not that kind of dirty!) and grouse about what you did. None of them actually attacked me.
Basically, story wise, your import has no real effect. The W1 was obviously not made with any intentions of taking your save and applying it to a future game by virtue of how and when it made a save, and it's obvious this was sort of tacked on to W2, probably because the big RPG elephant (*cough* Bioware *cough*) has almost single handedly made it an expectation for rpg gamers.
That said, the way W2 does your last save implies that this time around CPR fully intends to make your save mean something for import into future games. Plus, this time around, the game was very different based on your choices. I loved W1 to death, but let's be real, your decisions were pretty superficial in it. :p
The imported save doesn't affect the game THAT much, it is just details...
Raven's armor
The silver sword you had equipped at the time
Sigfried cameo
mentioning of Adda at different stages (Foltgest, to Shilard during the seige, Radovid, etc)
.. that's off the top of my head.
As for how choices work this time around, it is very different in W1, where your choices
lean you towards either pro-elf, pro-Order, neutral, whereas W2 is either this path or that path.