I have a problem with this workflow after updatering to El Capitan. Adding a task ('r something') freezez the Reminders App for some minute, after showing that it has added the reminder. Oddly, it also seems to make Reminders unstable after adding a single reminder, to the point where I need to reboot El Capitan in order to get Reminders working smoothly again (!).
As I've written before, this script is a key in my everyday workflow - thank you Jack for all your work with it!