DataTables 1.10.4 and Server Side Processing

Hello eveyone, it's already 2 days I am trying to sort a problem out, but I am not able to.

I am trying to use the new version of the dataTables, getting data from an asp.net webservice (VB). This is my HTML:

 <div class="container">
        <table class="table table-hover" id="liveTransactionTable">
            <thead>
            </thead>
            <tbody>
            </tbody>
        </table>
    </div>

This is my Javascript:

 $(document).ready(function () {
            $('#liveTransactionTable').dataTable({
                processing: true,
                serverSide: true,
                ajax: {
                    url: 'liveTransactions.aspx/getData',
                    dataType: 'json',
                    contentType: "application/json; charset=utf-8"
                },
                "columns": [
                 { "title": "masterProduct", "width": "160px", "className": "left", "orderable": true }]
            });
 });

This is my web service:

<System.Web.Services.WebMethod()> _
  <ScriptMethod(ResponseFormat:=ResponseFormat.Json, UseHttpGet:=True)> _
    Public Shared Function getData() As String
        Dim BIZTransaction As New Business.Transaction
        Dim transactionParameters As New Model.transactionSearchParameters
        Dim Transactions As List(Of Model.Transaction) = BIZTransaction.getLiveTransactions(transactionParameters)

        Dim liveTransactions As New liveTransactions
        Return liveTransactions.generateDataTables(Transactions)

    End Function
    Private Function generateDataTables(Transactions As List(Of Model.Transaction)) As String
        '' Generate the dataTable to be shown.
        Dim html As String = ""

        ' DataTables data.
        Dim dataArray(Transactions.Count - 1) As Object
        For Each Transaction As Model.Transaction In Transactions
            dataArray(Transactions.IndexOf(Transaction)) = New With {
                    .masterProduct = Transaction.masterProduct.Code}
        Next

        ' DataTables header.
        Dim jSonArray(0) As Object
        jSonArray(0) = New With {Key .sEcho = HttpContext.Current.Request.Params("sEcho"), Key .iTotalRecords = Transactions.Count, Key .iTotalDisplayRecords = Transactions.Count, Key .data = dataArray}

        Dim serializer As New JavaScriptSerializer()
        Return serializer.Serialize(jSonArray).ToString

    End Function

It's not working. Getting different errors. Can anyone help me please?

I know I am mixing versions, but I am jst trying...

Thanks,
D.