Is there any explanation of how Lyra gets from Svalbard in her world to Oxford in Will's world (in The Subtle Knife)? All subsequent travel between worlds through the windows has the traveler ending up in a corresponding location, rather than halfway around the globe.
At the end of Northern Lights/The Golden Compass, Lord Asriel opens a path between Lyra's world and the world of Cittàgazze (which is implied to be the city seen within the Aurora). The most detail we get on how Lyra made use of this path is in the beginning of chapter 3 of The Subtle Knife:
He carried the bowl outside and said, "If you don't come from this world, where's your world? How did you get here?"
"Over a bridge. My father made this bridge, and ... I followed him across. But he's gone somewhere else, I don't know where. I don't care. But while I was walking across there was so much fog, and I got lost, I think. I walked around in the fog for days just eating berries and stuff I found. Then one day the fog cleared and we was up on that cliff back there —"
She gestured behind her. Will looked along the shore, past the lighthouse, and saw the coast rising in a great series of cliffs that disappeared into the haze of the distance.
"And we saw the town here, and came down, but there was no one here."
It is in Cittàgazze that Lyra meets Will, who entered via a window in his Oxford, and it is afterwards through this window that Lyra reaches the other Oxford.
The explanation is given in a throwaway sentence near the end of The Amber Spyglass (Ch. 38):
Xaphania had told Serafina Pekkala that when all the openings were closed, then the worlds would all be restored to their proper relations with one another, and Lyra’s Oxford and Will’s would lie over each other again, like transparent images on two sheets of film being moved closer and closer until they merged—although they would never truly touch.
At the moment, however, they were a long way apart—as far as Lyra had had to travel from her Oxford to Cittàgazze.
So the worlds had drifted out of alignment because of the windows cut between them.