$tmpl_obj->param(
      LOGIN_URL => '/cgi-bin/Auth/Auth.cgi',
      EMAIL => $cgi->param('email'),
      PASSWD => '',
      RM => $nextrm,
   );
[download]

For this to generate an odd number of elements, $cgi->param('email') must return a list with an even number of elements. (It is the only method or function call; the others are scalars.)

In a list context (as this is), the param method will return a list. So, my guess would be that you have either zero or two instances of the 'email' parameter.

The simplest thing seems to be just forcing a scalar context:

   $tmpl_obj->param(
      LOGIN_URL => '/cgi-bin/Auth/Auth.cgi',
      EMAIL => scalar($cgi->param('email')),
      PASSWD => '',
      RM => $nextrm,
   );
[download]