The Exterior Backup controls where the Blade Plunges into the Matboard (not the Fallout) on the Exterior cuts of Openings.
The Exterior Cut is where the Blade Plunges or Retracts from the Matboard (not the Fallout).
If the Exterior Backup is cut Too Long, Decrease the Exterior Backup.
The Exterior Backup field is marked with a Green Arrow on the Configuration screen and the Map illustration.