There's really no advantage to using a form created in LiveCycle Designer for this. The restrictions are part of Acrobat/Reader, which is used to view both AcroForms and XFA forms.
You're already using a script, and it could be modified to save the file with whatever name you want and in any directory you want.
That tutorial is the best I know of, but you should also get the Acrobat JavaScript reference if you don't have it already. It's included in the free Acrobat SDK.