Fraktal Zero, its much easier than that.
ive made a copy of your event for grabbing and disabled yours so you can see whats different
--> added a "Trigger Once while true" to the Shift grab Keypress
This makes sure that its not a loop kept active by keeping Shift down
then
-->added a Timer to the Player detect "GrabTimer" every time the player does actually grab a ledge
its set to 4 seconds ..you can change this if you like
on the "Grabtimer" expring the Ledge Grabb Boolean is made false dropping the player
but can reactivate on each new shift press
Hope that helps
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