Do Range buffs apply to Powers that affect "a land with your Presence" or "one of your lands"?
No. "A land with your Presence" specifies a requirement for the land you're affecting (similar to, eg, "a land with Dahan" or "a land with Blight"), not a numeric Range. While it is usually the same in practice as "a land at Range 0", when using effects that modify Range the distinction matters.
For powers like Punish Those Who Trespass or Firestorm that have a base effect with normal range and a further effect referring to "lands where you have presence", the range on the base effect can be extended, but the further part cannot.
For instance, if you reach all the thresholds of Punish Those Who Trespass and have extended range, you can use the base effect to deal damage in a distant land and use the further part to deal damage where you have presence (without extension). (Discussion elsewhere) Tags: Range, Presence, Targeting, Reaching Grasp, 10 more...
Can Bringer of Dreams and Nightmares do real damage (destroying cities, etc) with Power X?
The answer, in general, is 'no'. If the Power says "damage" or "destroy", it doesn't matter if it also says that Dahan, Beasts, Invaders, or anything else are doing that damage, the source is still ultimately Bringer of Dreams and Nightmares and is only nightmare damage.
This applies even if the power has some other spirit doing something (eg, Blazing Renewal). If Bringer of Dreams and Nightmares played the power, it cannot do real damage.
