Should this only be enabled for escape and not all the time?
Yes please. It really makes vent camping in cade maps too easy. There's just no challenge anymore.
Oh, it's working alright. What the plugin does is it limits your ability to move forward (i.e gain any momentum) after jumping a certain number of times (as a zombie; it doesn't affect humans), which is the whole point of spam jumping in the first place. You can still spam jump, technically, but you can't get any momentum. It's less restrictive than GFL's anti-spam jump, for example, where the server completely freezes you from jumping at all for a few seconds if it detects any spam jumping, so you can still spam jump to reduce knockback.