Hi Tracy, I did get it working but I abandoned the path I was following, what I did in the end was load the data into a DataTable and used SetDataSource to feed it to Crystal

using System;
using System.Collections.Generic;
using System.Text;
using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Shared;
using System.Data;

namespace PassParamToCrystalandPrint
{
    class Program
    {
       static ReportDocument report;
    
        static void Main(string[] args)
        {
           
            report = new ReportDocument();
            report.Load(@"P:\Crystal\GetClaimsByMaster.rpt");

            report.SetDataSource(PKData.GetReportData()); // This static method returns a DataTable
            

            if (report.Rows.Count > 0)
                report.PrintToPrinter(1, true, 1, 1);

            report.Close();
        }
    }
}

It's not the preferred way but I really needed to get it working quickly - I tried all the Parameter refresh and lots of other stuff but none of it worked - feel free to help me on this :-)