CRM 2011 Create a new Case (incident) using C#

using System;
using System.ServiceModel;
using System.ServiceModel.Description;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Client;
using Microsoft.Xrm.Sdk.Query;
using Microsoft.Xrm.Sdk.Discovery;
using System.Runtime.Serialization;
namespace CreateIncident
{
    class Program
    {
        static void Main (string[] args)
        {
            try
            {

ClientCredentials credentials = new ClientCredentials();
credentials.Windows.ClientCredential = new System.Net.NetworkCredential

("username", "passw", "domain");

Uri organizationUri = new Uri("http://crmservername:port/orgname/XRMServices/2011/Organization.svc");
 

Uri homeRealmUri = null;

OrganizationServiceProxy orgService = new OrganizationServiceProxy(organizationUri, homeRealmUri, credentials, null); 

IOrganizationService _service = (IOrganizationService)orgService;
                              

Entity incident = new Entity(); 

incident.LogicalName = "incident";
 

incident["title"] = "Case subject..";
 

// Set customerid with some existing contact guid 

Guid customerid = new Guid("{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}");
 

// Set customerid as contact to field "customerid" 

EntityReference CustomerId = new EntityReference("contact", customerid); 

incident["customerid"] = CustomerId;
 

// Set contactid with some existing contact guid 

Guid contactid = new Guid("{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}");
 

// Set contactid as contact to field "casecontactid" 

EntityReference primaryContactId = new EntityReference("contact", contactid); 

incident["casecontactid"] = primaryContactId;
                                                      

_service.Create(incident);

            }
            catch (Exception e)
            {
                Console.Write(e.ToString());
            }
        }
    }
}