That means that the KM script hasn’t yet created the relevant variables
I’ve just downloaded the copy above and successfully run it from KM:
I suggest that you:
- Delete the copy currently in KM
- Download and install again
- Try to run it
- Then try a different hot-key to launch it (in case of some clash)
- and also run the dialog action with the KM Try button to make sure that it is creating the set of variables
(You can inspect the variables which KM knows about through the KM menu system: Preferences > Variables )