In SR3, followers of the "totem way" could use astral quest for initiation only. I was thinking of using this in SR4, since the ability is limited in use and purpose. Also, instead of power (initiation grade, metamagic) perhaps the totem could offer information. I was looking for a way to link ED and SR. The mentor could offer glimpses of past ages, or of important events such as Dunk's assasination. These could be represented as a knowledge skill, say....

Knowledge (Fourth World)

1 would be what an average Barsavian knows, 3 what an average adept/adventurer knows, 6 what a powerful ruler (Neden or Alachia) would know, and the max of 7 reserved for GDs and IEs.

I don't quite know what to call the other one; perhaps "Conspiracies (Sixth World)". How to represent player knowledge of metaplot? Is a game mechanic even necessary? Comments/suggestions welcome.

As the "Mentor Spirit" Quality is not available for Adepts, it's not possible at the moment to follow the Totem Way. Personally, I would simply allow the "Mentor Spirit" quality and thus also the "Astral Quest" for initiation. I don't really see a problem here

Knowledge of the fourth world would be best got from someone like Harlekin, Ehran or a dragon. As it will probably be not important anymore - Earthdawn and Shadowrun have different publishers now - it's probably a rather useless skill
Anyway, simple taking a Knowledge skill seems a little bit "not enough" to me...

Yeah, trying to pigeonhole the metaplot into a knowledge skill is probably an excersise in fultility. But I'm attracted to the idea of a character who has significant pieces of the puzzle, so to speak. The mentor spirit thing is iffy. Both Synner and Rob have said that adepts can have them; apparently, the lack of adepts in the positive quality is a misprint. Even so, Street Magic says that only full magicians or characters with access to the Astral Gateway power of a free spirit can use astral quest. But I don't see a problem bending the rules a bit, provided it's only used for ordeal purposes. Or maybe the adept could develop a magical compound allowing him to do the equivalent.

Page 192 doesn't contradict Page 79. Any character with "Mentor Spirit" quality doesn't include "adept" And I can't find that sample character in my core book...

But personally, I don't see why adepts shouldn't have mentor spirits. It's not even powergaming, as at least 50% of the advantages don't even help the adept So I quite agree with the official answer.