using nlapiSetRedirectURL to initiate a new event

I am trying to initiate a new event record using a redirect from an existing event record.  The script will pass parameters to set some of the values on the new record.  I have successfully submitted a new event record and redirected to it.  However I would prefer not to submit the record until the user has had the opportunity to edit the new record and save it manually.  I found the following example code snippet in SuiteAnswers and  it seems to be designed to do what I want it to do.  However the params value seems to do nothing