Pass a parameter to a crystal report in vbscript

I added a button to the SO invoice entry screen with a VBscript attached:

Set Report = CreateObject("Sage100ERP.Reporting.Report")
Report.Load("C:\Sage\Sage 100 Advanced ERP\MAS90\Reports\SO_Report_custom.rpt")
connectionString = "DSN=SOTAMAS90;UID=reports;PWD=reports;Company=ABC"
Report.SetConnection connectionString
Report.Preview()

I want to pass the batch number to the crystal report so that the report only runs for the batch that is selected.

The report runs fine, except I cannot pass the batch number to the report.

I have searched this forum, the KB and the interweb but cannot find an answer.