Unfortunately D2:ED saves are not compatible with DKS. I'm planning on going through DKS with a different character anyway, but would have preferred to be able to continue with my existing character.
There has not been any mention of importing saves. At least theoretically it might be possible to import a character from a save at the end of the hall of echoes, since presumably there wouldn't be as many chances of conflicts if you are not going back to D2:ED locations; I don't know if changes to item generation, or something, would cause a problem anyway, though.
In D2:ED + FoV it will be possible to start a new level 35 character to start at the beginning of the add-on. Maybe DKS will include that option, as well.
