Just want a bit of advice; I would like to have a back in my button in my application. what way would be the most effective to add a back button that would work across the application.
are you wanting to go the previous layout? You can use the OnLayoutExit trigger to fire a script that stores the layout name or number in a global variable. You'd need to add this trigger to all layouts.
Have a look at my session from FileMaker DevCon this year. There is a video + material to download on how to handle your problem
WEB002 - Prepare Your Custom App for FileMaker WebDirect - Johan Hedman
I've found the method detailed on Modular Filemaker to be pretty robust:
Why do you want a back button?
You want to step backwards through committed orders, for instance, and change them?
Presumably this is a database application.
Think seriously about what a back button really means.
Retrieving data ...