Application Licensing using the .Net Framework (C#)

Question

I want to use application licensing feature of .Net which will require valid license to run the application, .Net provides two ways for doing it, I want to use the option which uses Registry. Can any of you help me on this. Or can suggest some web link where i can get some material Application Licensing using .Net. For further details on this u can visit www.developer.com/net/csharp/print.php/10918_3074001_3 this will give u better idea of what i want to implement. I tried on the sample application given on that site but it does not work.