Hi Tim,

Here is the source for the default export to csv one

 public class ExportToExcel : ExportType {

        public ExportToExcel() {
            this.Description = "Exports all data to a csv file";
            this.Name = "CSV File";
            this.Id = new Guid("94ED105A-87B3-4e1f-97CB-9A320AEE2745");
            this.FileExtension = "csv";
        }

        private string xslt = Configuration.Path + "/xslt/excel.xslt";

        public override string ExportForm(Form form)
        {
            RecordsViewer rv = new RecordsViewer();
            XmlDocument xs = new XmlDocument();
            XmlNode XmlRecords = rv.GetXmlRecords(form, xs);
            rv.Dispose();

            return XsltConvert(XmlRecords, HttpContext.Current.Server.MapPath(xslt));
        }
    }