If I add:
{ASK DATE1 "Date1?"}
{ASK DATE2 "Date2?"}
Just after the '{QUOTE' line, and input various dates, the field code works just fine. That suggests an error in your implementation. Perhaps you'll get better results if you copy the field code from my post into your document, then convert it to a field using the macro here:
http://www.gmayor.com/export_field.htm#TextToField