Hello danjut,
The source code download is for the controls, not the samples. To build the samples browser locally, please download the Samples Browser from this page. The "NetAdvantage for ASP.NET 2010 Volume 3 Samples" download will give you both a Start Menu shortcut to launch the samples browser locally, and also the source code for the samples so you can build them locally.
Let me know if you have any other questions about this.
Elizabeth AlbertLocalization Engineer