I'm sure the debate still rages somewhere, but what has been accepted as a "ranged" attack. does the 5+ ward extend to spells that target a unit inside the bubble? Certainly all shooting attacks from missile weapons and war machine counts, but I was curious about magic in particular.
The portent of warding description only includes wording about "any ranged attacks". Since there is no specification or limitation to the shooting phase, it would encompass all shooting attacks, magic missiles and direct damage that originate >>12" from the engine. Note that some direct damage spells would ignore the warding due to the wording of the spell (i.e. pit of shades).
Of note, direct damage spells have ranges, hence they are a "ranged attack". Also, one of the main FAQ questions indicates that "ranged direct damage spells" exist as follows: Q: Do ranged direct damage spells that use a template have to target an enemy unit? (p31) A: Yes, the template must be placed over the target enemy unit. This isn't to say that your group will agree but at least it provides some evidence to support the ranged attack definition.