When Layouts or Scripts are edited, I don't think there is an automatic way to know that they have been edited. If that is what you are asking about.
If not, please exand on what you mean.
On the opening screen of my application I have a Date Last Edited/Version No text field. Which relies on me remembereing to update it whenevr I make a change to a layout or a script, and I don't always.
What would be nice is for the main initialisation script to be able to update the field automagically.
But it looks like it might not be possible.
You can use an OnOpen script, then you can add a Set Field step to enter in the current date or time. That would activated each time you open your file.
Set Field [ dateField ; Get ( CurrentDate ) ]
Set Field [ timeField ; Get ( CurrentTime ) ]
I forgot to mention:
File -> File Options (on a Mac)
How would that tell me the date time the layouts or scripts were last amended?
Well, since you said,
main initialisation script to be able to update the field
I thought maybe you wanted the OnOpen Script that runs each time you open the file to fill in the date and/time you edit a layout. I apologize for not understanding.
It seems that you probably will have to do it manually like you have been.