I'm on mac with a non-mac keyboard.
I can get it to work if I activate Excalibur, type the command name, press numpad enter, then numbers, then numpad enter.
however If I activate excalibur, type command name press normal enter (which is natural for me as it's closer to the keys), then switch to the numeric keypad and enter number, then press numpad enter, it seems like it does not work.