In my case I have not used the //!, because I found it annoying when opening the script for editing it would have executed all the time (I often forgot ...).
Instead in Win10 using Task-Scheduler, and adding JMP.exe as Program and the script path as optional argument, JMP executes the script in defined way, so "//!" is not needed. Of course, the script needs to close JMP after finishing ( Quit(); ).
Georg