Stencyl : Simple Dialog Box

Dialog Screen

Create a scene that is larger than the display-screen.

Put a button on the first part of the scene 'top dialog'

Button pressed on actor:

[move [camera] to (x:0 y:1400)

Put another button the second part of the scene

Another button

Pressed on Actor:

[move [camera] to (x:0 y:0)

Now you can switch between the 'dialog' screens.