Where and how to code Doc.saveAs() method

I’m developing a fillable form with drop down list, data connection, signatures and everything in Adobe LiveCycle Designer … and I want to have a button to save a copy of the form once it is completed. I put the following code in the click event of a button:
 
mySaveAs = app.trustPropagatorFunction(function(doc,path)
{
app.beginPriv();
doc.saveAs(path);
app.endPriv();
})
myTrustedSpecialTaskFunc = app.trustedFunction(function(doc,path)
{
// privileged and/or non-privileged code above
app.beginPriv();
mySaveAs(doc,path);
app.endPriv();
// privileged and/or non-privileged code below
});
 
myTrustedSpecialTaskFunc(this, "/c/jesus/mySavedDoc.pdf");
 
But I’m getting the following error message:
 
NotAllowedError: Security settings prevent access to this property or method.
 
I read some Java Scripting documentation and I understand that there are different levels for Java Script: folder level, application level, form field level.
 
Where do I have to put the code in order to have the results that I want? What else I have to do?
 
Please, try to explain that to me as If I’m seven years old boy :=)
 
Thanks