Editor Update Issue

Hi DataTables Team

Just started using my 15 day trial of the editor, fantastic piece of work guys - but ...... I can insert and delete fine but on update I get the following message:

Notice: Undefined offset: 0 in /var/www/hub.citygate.co.uk/wp-includes/DataTablesEditor/php/lib/Editor/Editor.php on line 544
{"id":"row_","error":"","fieldErrors":[],"data":[],"row":null}

Everything's OK using the generator, only difference here is that I'm using an existng dataTable and adding the editor:

var $j = jQuery.noConflict();
$j(document).ready(function() {
    // $j('#tHdr').css('background-color','#dddddd');
	
	editor = new $j.fn.dataTable.Editor( {
        "ajaxUrl": "/wp-includes/DataTablesEditor/php/table.hub_nps.php",
        "domTable": "#tGrid",
	 "idSrc": "id",
        "fields": [ 
			{
				"label": "id",
				"name": "id",
				"type": "readonly"
			}, {
                "label": "Date:",
                "name": "date_visit",
				"type": "date",
				"dateFormat": "dd/mm/y",
				"dateImage": "images\/calender.png"
            }, {
                "label": "Employee:",
                "name": "employee"
            }, {
                "label": "Score:",
                "name": "score"
            }, {
                "label": "Comments:",
                "name": "comments",
				"type": "textarea"
            }
        ]
    } );
	
	
	
	$j('#tGrid').dataTable( {
		 "sDom": "Tfrtip",
		"iDisplayLength": 100,
		"aaSorting": [[2,'desc'], [1,'asc']],
		"aoColumns": [
		{ "bVisible" :true, "mData": "id",         "aTargets":[0] },
		{ "sWidth" : "10%",   "mData": "date_visit", "aTargets":[1] },
		{ "sWidth" : "20%",   "mData": "employee",   "aTargets":[2]  },
		{ "sWidth" : "8%",    "mData": "score",      "aTargets":[3]  },
		{ "bSortable": false, "mData": "comments","sWidth" : "62%", "aTargets":[4]  }],
		"oTableTools": {
            "sRowSelect": "single",
            "aButtons": [
                { "sExtends": "editor_create", "editor": editor },
                { "sExtends": "editor_edit",   "editor": editor },
                { "sExtends": "editor_remove", "editor": editor }
            ]
        }
	});

And here's the PHP:

<?php

/*
 * Editor server script for DB table hub_nps
 * Automatically generated by http://editor.datatables.net/generator
 */

// DataTables PHP library
include( "lib/DataTables.php" );

// Alias Editor classes so they are easy to use
use
	DataTables\Editor,
	DataTables\Editor\Field,
	DataTables\Editor\Format,
	DataTables\Editor\Join,
	DataTables\Editor\Validate;


// Build our Editor instance and process the data coming from _POST
Editor::inst( $db, 'hub_nps' )
	->fields(
		Field::inst( 'id' ),
		Field::inst( 'date_visit' )
	->validator( 'Validate::dateFormat_required', 'd/m/y' )
	->getFormatter( 'Format::date_sql_to_format', 'd/m/y' )
	->setFormatter( 'Format::date_format_to_sql', 'd/m/y' ),
		Field::inst( 'employee' )
			->validator( 'Validate::maxLen_required', 100 ),
		Field::inst( 'score' )
			->validator( 'Validate::required' ),
		Field::inst( 'comments' )
			->validator( 'Validate::required' )
	)
	->process( $_POST )
	->json();

Here's a link to the page (I'd removed the date field in case it was something to do with dd/mm/yyyyy formatting):

http://hub.citygate.co.uk/?page_id=126

Any ideas? It looks like the row number is not getting passed.

Many thanks

Andy