C#+Crystal+Parameters+Record Selection = headache

Question

Good morning folks

I have a simple crystal report with only one parameter field and this field is attatched to the report's record selection.

It works fine if I preview the report and type the value in the discreet value box.

My problem is that i have a form with a Crystal Report Viewer and i want MY application to provide the value for that parameter but i can't find anywhere over the web how to do it..

it seems simple but it's killing me...

someone please help?