Crystal Reports Record Selection Questions

Question

Hi to all!

I have following problem:

In my application (Visual Studio 2008 - C# language - I AM NEWBIE AT C#), I have two GUI elements - date pickers (MonthCalendar class) and according to their selected values (dates) i would like to filter records in report. I've added parameters (dtDateFrom, dtDateTo - both of type DateTIme) to report and now:
1) How do I dyinamicly setup their values to contain values from previously mentioned MonthCalendar classes (I've setup event handler, tested it and it works fine) - the question is, how to fill report parameters?
2) How do I then refresh report to show new data?

Currently, the second problem is:
As I lanuch app or press "Refresh" toolbar button on report, I get date entrance window, which is invoked from Crystal Reports - HOW DO I DISABLE IT?

Please answer ASAP since I am in hurry and thanks in advance for answers!

Sincerely yours,
Marko