Yes.
Yes, she can. The distance to the dragon is 1, and that's what matters. The dragon's range number never determines whether you can attack it. It only determines whether the dragon can wound you if you attack and lose.And from another room we don't count range as 1 room and 6 from the dragon = 7? Haley with Ranged Attack 4 can Attack from the room next to the one that the Dragon is?
For example, Vaarsuvius with a fully-boosted Lightning Bolt has a range of 7. So V can attack from 7 rooms away. If V loses, there's no wound, because the dragon doesn't have enough range to reach V. (Rulebook page 12, second bullet under "Ranged Defense".)
Maybe I don't understad your original question. Can you rephrase it?#2 You mean that Horde = Undead or I don't get the point?