how to force the form not to close / customize the messagebox at save time

Hello all!

I'm using AEM/designer to design a form, at the time a user clicks red cross to close the form--> "Do you want to save the form <form name>?" Click save button --> save the form --> enable validation script and pop up warning message at form presave event.

questions:

1. how do i customize the text "Do you want to save the form <form name>?"

2. if he clicks save button and the form is saved and pops up warning message that some fields are empty, he clicks "OK", how can i keep him stay on the form?

on the internet, i can only find script to force one to close the form:

event.target.closeDoc(false); // or param value = true

app.execMenuItem("Close"); 

But I cannot find one script to keep the form open. Is it possible or not?

Thank you in advance!