Not sure what you're asking: if you run a subscript that exits with a result, you can refer to the result back in the calling script as:
Script parameter has nothing to do with this.
i've never used this so I was unfamiliar with the differentiation of Result and Parameter
I consulted the help but sadly they show how to send back the result, but not that script step of Get (ScriptResult) which I am eager to try out. (Silly they!)