public string Export(string url, Workflow workflow, string path)
        {
            var nintexService = new NintexWorkflowWS
            {
                Url = string.Concat(url, NintexServiceUrl),
                Credentials = CredentialCache.DefaultCredentials
            };

            if (!SpContext.IsFeatureActivated(url, NintexWorkflowFeatureId))
            {
                throw new Exception(string.Format("Web feature \"Nintex Workflow 2010\" is not activated for the site {0}. Please activate and try again.", url));
            }

            var workflowXml = nintexService.ExportWorkflow(workflow.Name, workflow.ListName, workflow.Category);
            var localFilePath = SaveWorkflowXmlToFile(workflow.Name, workflowXml, path);
            workflow.Serialize(localFilePath);
            return localFilePath;
        }