Warlord Bravura Presence and multi-target attacks

What are the rules for when the ally of a warlord with Bravura Presence uses their action point for a multi-roll or multi-target attack, e.g. Twin Strike or Winged Horde?

When an ally who can see you spends an action point to take an extra action and uses the action to make an attack, the ally can choose to take advantage of this feature before the attack roll. If the ally chooses to do so and the attack hits, the ally can either make a basic attack or take a move action after the attack as a free action. If the attack misses, the ally grants combat advantage to all enemies until the end of his or her next turn. (Martial Power p. 103)

If I’m targeting three creatures with Winged Horde and I hit two of them, did the attack hit, miss, or both? Does it matter in which order I hit them?

Same question if I’m targeting the same creature twice with Twin Strike – one hit, one miss. (The relevant phrasing here is Attack:[..], two attacks)

What if I’m using Synchronized Strike? (First a beast Attack with Effect: secondary attack; also, who would grant CA?)

And how does the feat Improved Bravura affect that?

Benefit: When an ally uses your Bravura Presence, that ally gains either a +1 bonus to the attack roll or a +1 bonus to speed for the move action (the ally’s choice). (Martial Power p. 136)

Is that for all attack rolls in the aforementioned scenario’s, or just the first one?