PDF Javascript Issue With Date Selector

The first observation is that this PDF was created in Adobe Illustrator and exported to PDF.

It has a few design glitches and is acting very sluggish.  

The second observation is the scripts used to calculate dates are incorrect.  If you're using util.scand to process a date  object, once you're done applying your date script calculations,  you need to convert it back to a date string  object with util.printd or it won't work correctly.

You're also missing the appropriate arithmetic between  year, month, days, hours, minutes and miliseconds for accurate results.

Here's an example:

var LoanClosed = this.getField("DateLoanClosed").value;
var remaining = this.getField("RemainingYrs").value;
var d = util.scand("mm/dd/yyyy", LoanClosed);  
    d.setDate(d.getDate() - remaining);  
    event.value = util.printd("mm/dd/yyyy", d);  

And in order to calculate the correct difference in days between two dates you need  a different script.

You won't need a validattion script if you apply the correct arithmetic and use a date picker for the users, don't let them enter a date manually , unless you apply an arbitrary mask if there's a need for entering dates manually on each field.

The script below calculates difference in days between two given dates:

var strStart = this.getField("StatementDate").value;
var strEnd = this.getField("DateLoanClosed").value;

if ( ( strStart != "") && ( strEnd =="") )event.value = "day(s):"

 else if(strStart.length && strEnd.length)
{
  var dateStart = util.scand("mm/dd/yyyy",strStart);
  var dateEnd = util.scand("mm/dd/yyyy",strEnd);
  var diff = dateEnd.getTime() - dateStart.getTime();
  var oneDay = 24 * 60 * 60 * 1000;
  var days = ("day(s):");

  if (diff < "0")  event.value = "";
  else event.value = days;
  
}

else event.value = "";

It would be easier if you just reflect the difference in total month remaining , not year +months which is why you're getting the errors.