You are welcome, I am sorry you are having errors.
I have hunted down the specific problem you were having, and tested the plugin command and its functioning fine now in V1.21!
You follow instructions really well, the script call would have worked if I wrote my instructions properly, I forgot to include that when you write :
ssa
in the script call, it should be surrounded by quotes so its a string, like "ssa", but the plugin command can be just ssa
Thanks for reporting the issue, let me know if you have any more. :)