[gurps] Portals

[Chris]

Heres hoping someone can give me a bit of clarification, an answer or at least a plausible reason.
I am currently running a fantasy game and have had the party of delvers find an underground circular room that gives a lovely panoramic view of the world outside above ground, just beyond this informational illusion is a wall with corridors leading off at cardinal points.
What one sneaky delver is currently seeing in the panorama from a hidden vantage point is a Lich pointing an amulet into the room from outside allowing his minions to enter the room to head to the barracks.
This amulet only works one way, allowing the lich to point the way for his minions to go ahead of him to ensure his safety.
What one of the players wants to do is use apportation from inside the room to snatch the amulet from the Lich who is outside.
Technically, the Lich is actually about 1,000 yards higher and a good 2 miles further north.  From the delvers point of view, the Lich is about 7 yards away.
Q1. Would apportation work the wrong way through a one way portal.
Q2. What range penalties should I be using.

As a thank you for any information forthcoming, here is a little setup I used on the players earlier on today.
The delvers enter a corridor of patterned stone about 20 yards long with a door at the end.
The mage in the party or at least someone with "See Secrets" finds there are 4 doors hidden in each side of the corridor and the door at the end is locked, trapped and magically warded.
The hidden doors are unlocked and untrapped and open easily when something is used to wedge them up high enough to get some strong hands under.
The door at the end of the corridor, which will occupy the delvers for some time is just an extremely artful carving and is just part of the wall, the traps and lock are just bait to occupy and frustrate them.
The only way beyond this point is another door hidden in one of the hidden rooms.
The Minotaur in the party suffered a broken shoulder and a major concussion on this one.  Happy days!