These questions from the GLoAQ are basically already included in the FAQ 2010, although the wording might be different.

In some questions, a few nuances did not make it into the FAQ, so this is the place to probably discuss the need to amend or extend the current FAQ wording.

Some of these questions give answers that are contradictory to the current FAQ - I included them for reference.

If discussing any question, please use the numbering to get a clear assignment.

1. Can heroes hit each other with knockback to gain MP - purposely limiting their damage as to not damage the friendly in the process? purposely limiting their damage as to not damage the friendly in the process?

Heroes can attack one another. However, the only way they can "limit" their damage is by opting not to spend surges or by spending power enhancement results on range rather than damage. (Or by Aiming, I suppose.) If you roll seven hearts on the red and green die, that's still seven damage dealt to your buddy...
Also, note that knockback does not give anyone MP. It simply throws the target around. The subject can't use the knockback move to, for example, drink a potion.

One last comment: when the hero "comes to rest" after a knockback, he's a valid target for Crushing Block, Pit Trap, Aura damage, pit obstacle damage, and similar effects, so this is a very risky maneuver for a low-health subject.

2. Can a hero target a square with another hero in it? e.g. If he wants to use "Blast", and the target hero is willing to risk taking damage. Or, if a hero wants to remove the "Sleep" effect token from another hero.

Yes

3. Does the OL have to continue his same course of action when interrupted by a guard action?

The OL may change his mind after being interrupted. (…) the OL can change his mind after being interrupted, (…) treat it as though you did a little 'rewind' to right before he declared an attack. The OL, after being interrupted after declaring an attack, may choose to continue with the attack, change its target, or even not to make the attack at all. (Edited to keep the context of the answer)

4. Can a figure with both Reach and Sweep hit a target through another figure?
Clarification: Can the attacker choose which targets die first in a sweep, thus possibly clearing a way to a further target? (see also LoS)

Yes, this is intended to work as though line of sight ignored figures for Reach/Sweep.

5. When using the Leap attack, are Blood Apes affected by Aura? Also, are they affected by abilities such as Alertness and Guard orders, which can be triggered by a figure moving next to the Hero with the ability?If the Ape is affected by Aura when it has Leaped, does it gain the benefit of it's Enrage ability from the Damage taken?

No, No and No.

6. Does the Appraisal skill also work on treasure bought in town?

Yes.

7. The two half actions given by the leadership card, do they have to be different half actions, or could you "Attack" twice?

Actually, when using the Ready action, you can't select the same half action more than once. The wording is a bit confusing, yes. But you can move, attack, and place an order, or move, place order, and concentrate, or whatever. Just no double attacks or double moves or whatnot.

8. Can LoS be retraced during an attack? Such as with Sweep, above. If the targets can be killed in front of him during the sweep attack, is the target at the rear of the group open to be attacked by the same Sweep attack?

Yes, remembering the ruling on Reach/Sweep from earlier.

9. Are the curse tokens that are placed on Heroes able to be removed by abilities (such as with Sahla) or the Cursed Doll? If so, does the removed Curse token refresh only when the item is re-equipped?

Curse tokens are a lingering effect token like any other. Sahla and Curse Doll can both remove them

10. Can the hero party attack multiple Lieutenants and visit a city in the same game week action?

Yes, but they may visit the town only after all Lieutenant battles have ended.

11. Can a hero rest in town, or are they restricted only to restocking benefits?
Can a hero take any action before he goes to town after beginning his turn next to a glyph?

This is part of a larger question, which is basically "How does Town and/or Glyphs work?" The short answer is, "no, heroes can't rest in town." The longer answer is below…
A hero who begins his turn adjacent to or on top of an activated glyph has two options: take a normal turn or go to town. If he goes to town, he is immediately moved to the building of his choice and gets to Restock there. No movement points, no declared action – he just Restocks.
A hero who begins his turn in town has two options: Restock again (at the same or a different building) or return to the dungeon. If he returns to the dungeon, he declares a normal action (Battle, Ready, Advance, Run) and then must spend a movement point to move from town to the dungeon, just like normal. If he somehow can't do so (i.e. he Battled and had no fatigue left) then the entire action is canceled and the hero Restocks instead. .

12. Can the heroes Visit buildings, purchase Tamalir upgrades, or fight lieutenants if the party marker is placed in Tamalir after ending/fleeing a dungeon

No.

13. When playing dungeons in RtL does the OL keep his cards, powers and Threat between levels?

You keep your hand, threat, and power cards for the entire duration of a dungeon. You do not reset those between dungeon levels. I'll have to look at that section of the rules to see exactly what it says, but if it says that you reset every level, it will have to be errata'ed.

14. Are lieutenants considered an Avatar upgrade, e.g. Can they be purchased before the game starts?

It was not my intention that the OL be able to purchase Lieutenants with his starting free 15 XP. The heroes need a couple of turns to get into the swing of things. So no, you cannot purchase extra Lieutenants to start the campaign.

15. KW came and gave some info on how he currently thinks Feats should work in RtL. I got the impression that Feats were not originally intended for use in RtL. Quoting KevinW from that link:

"Jason and I were talking this over, and for now, I'm going to recommend you give them one feat card of the same type as the skill they keep at the start, and then just playing it normally, but carrying the same hand of feats through the whole campaign, drawing one new card each time a glyph is activated. They can still draw feats from any deck corresponding to a skill they have at least a 1 (or an actual skill card) in."

16. Stairwell. Let's say I have a character who can attack with a blast weapon. She is standing on a stairwell and has line of sight to the corresponding stairwell as well as the adjacent spaces. If she fires at one of the adjacent spaces, and gives it a total of Blast 4, does the blast travel back through the strairwell?

Yes.