Consider the following text:
Tania is in her living room, in the summer. She looks to the window and the street in front of her house, then she realized how dry and parched they are, this makes her sadness even worse. After a labor day of house work, she decides to take a nap, which turned up to a long sleep. During her sleep, she dreamed about her mother, telling the origin of silver forks of the kitchen. In her dream her mother told she that the silver forks were from her grandmother and lots of other things like fact that they were originated in Italy. Waking up, Tania looks again to the street and realized how wet they are, and how the temperature are better now. After saw the streets so clean and beautifully wet, she have never been sad again.
Well, it's clear that the event here (or more precisely, the story event) is the rain. The value (sadness, happiness) changes as we expected. This is a true story event.
Now, concerning Tania's dream, this dream would be a larger event, even a sequence or an act if you wanted. But this dream didn't change anything, and if we eventually build a scene (or a large structure, as I said, a sequence or a act) this scene would not satisfy the Mckee's point of view that "every event must to change".
But, Tania's dream gives the character's story more information and also descriptions about her world. If we eventually build a scene, then this scene would work as a "descriptional or expositional" structure. Mckee suggests this on page 36 of .
Is it correct to treat a scene like Tania's dream this way, i.e., constructs a new kind of structure just to do description?
 MCKEE.R. Story. itbooks. New York, 1997.