Super Mario Bros. X Forums

(Note: Section should be replaced with whatever section the autoscroll is in, and Speed should be replaced with the autoscroll speed. The Table of Values shows you which number makes which boundary move - 0 and 1 for a vertical scroll, and 2 and 3 for a horizontal scroll.)
Table of Values (from the LunaDLL tutorial)
0 = Top border
1 = Bottom border
2 = Left border
3 = Right border
Step 1: make sure you actually have LunaDLL
Step 2: make a lunadll.txt in your level folder and put
#Section
PushScreenBoundary,Section,First Boundary,0,0,0,Speed
PushScreenBoundary,Section,Second Boundary,0,0,0,Speed
TriggerSMBXEvent,0,0,0,0,1,Scroll
#END
Step 3: Make a SMBX event "Scroll", that sets the screen boundary to one screen - like you would with the regular autoscroll - and then move them back to where they once were in your whole level
Step 4: The "TriggerSMBXEvent" triggers the position event, and the "PushScreenBoundary" autoscrolls the screen! Tada!
Here's a level download for an example level:
https://www.mediafire.com/?i1o8k0uo8ti1uwo

You can use "LayerXSpeed,0,1,0,0,1,0" so that the edge of the screen crushes the player.
Also on the version I currently have, it is possible to change the time the autoscroll is active.

For example, triggering this custom event once starts autoscroll with speed of -2 on section 1 for 200 frames.

#2000
LayerXSpeed,0,1,0,0,1,0
PushScreenBoundary,1,2,0,0,200,-2
PushScreenBoundary,1,3,0,0,200,-2