crystal reports help

Hi, I am building a crystal reports 11 report and need some help. The report has a date range as a parameter which I want to keep as is. It also has a stored procedure as a datasource with 2 date parameters. I want the users to be able to select the date range using the calendars and it passes the values to the parameters for the stored procedure. So at the moment the report has 3 parameters , 1. Date Range ( I want to keep this) 2. @DateFrom ( want to pass the minimum from Date Range not have it prompt ) 3. 2. @DateTo ( want to pass the maximum from Date Range not have it prompt ) more detail in detail section.... ## Deliverables example of how to called the stored procedure EXEC [dbo].[QReport] @DateFrom = N'2011-04-01', @DateTo = N'2011-05-01' EXEC [dbo].[QReport] @DateFrom = NULL, @DateTo = N'2011-05-01' EXEC [dbo].[QReport] @DateFrom = N'2011-04-01', @DateTo = N'2011-08-01' EXEC [dbo].[QReport] @DateFrom = NULL, @DateTo = NULL you can give me a sample report that shows how to do this or give me instructions on how to do it. The report is not written yet or stored proc so make a example if you need to .