if you are a novice, you might find some of the interface misleading.
Like where it says "program/script", for example!
Dont just be putting in your script there… its not gonna work.
If you want to run an applescript, you better put put this:
osascript /yourpath/yourscriptname.scpt
and be sure to check the box "arguments" - the script path and name is an argument passed to the osascript PROGRAM.
(if yer a Mac noob like me, you might not know that osascript is the program that executes the applescripts…)
Anyway, after digging into system error logs, and after much Googling, I was able to figure this out, and get it running.
And if you are as MacNoobnificent as myself, be warned that wherever your script lives, you need to make sure it has executable permissions.
I did this via the console, cding to the folder where i put the script, and fixing up with chmod 777 MyScriptname.scpt ( and also chmod -x MyScriptName.scpt - just to be on the safe side).
Once I got all that sorted, the LaunchD Task Scheduler worked just as advertised...