That explains the confusion. You could put the handler in the stack script if you want, but then you'd need to specify which card it should be operating on. By default it will look at the current current card and if that happens to be Menu then the objects won't be found.In FileMaker all the scripts are together, it is as if they were in the stack script
I think you're on your way but write again if you need to. We're always happy to give a leg up.