Possible Clues:

• Detach, as a fence gate
• Make fast? On the contrary (one local runner)
• Free upper-class knight, one that may be shot
• Prepare to swing open
• Lout made a mess of covering note to open gate?
• Open, as a gate door
• Open, as a door lock
• Release, as a door lock
• Open, as some doors
• Open a French type of sandwich with nothing in it