I added the script from the video posted in 2018 and it doesn't activate the soft limits.  I checked the script for the Ref All Home button and it only has RefAllHome() in it.  Did the coroutine script get removed in a later version of Mach4?  I can't find what it should be anywhere.  According to the new script there should be something for the coroutine in it, I thought.

----See ref all home button and plc script for coroutine.create and coroutine.resume

It is in the screen load script; you add it to the code there.
To get to it, see attached picture.
Open the script and search "refall"; you'll find the code that is embedded in the RefAll button.
modify the script there.  You can't modify the script in the button since this edited script adds the "sefsoftlimits" fuction.