Focus Dreams

TMRE refers to Magical Focus (Dreams).
Would that be a major or minor focus?

Presumably, given that they list Affinities and Puissance alongside them, it does the same thing that 90% of Mystery Cults do with Potent/Focus, i.e. you get the Minor version, unless you already have it, in which case it's upgraded to Major.

I'd guess I'd have to say Major. Although dreams are, but a tiny facet of what Mentem is capable of, they can be affected by any of the five Techniques.

The same is true of several Minor Foci, though. Heck, Anger is a Mentem Minor Focus that could probably be affected by any Technique. Auram's examples, especially Wind, all share the trait of being affect-able by all Techniques. It's about actual scope, not just how many TeFos can be used. (Although with the new Dream Magic rules, I suppose a Dream Focus could, under certain rulings, be quite broad.)

I'd say it's minor, with the tautological caveat that it will be incredibly useful in manipulating dreams - which is easier to make the focus of an adventure than, say, having a minor focus in cabbages. (Cabbage Quests aside.)

Minor or Major? I'd say probably Minor, in that a Focus in Dreams is generally far less broad than one in Emotions or Memories - though it could be argued that it's broader than Lust or Sorrow. Note that in any case I would not allow it to apply broadly to magic cast while in a Dream (as per the Dream Magic mystery) - only to magic that (creates or) targets dreams.

Oh, sure - that would be "Special Circumstances (when dreaming)", for a +3 bonus. Nice secondary virtue to have if it's your specialization. Otherwise? Not so much.