Drag and Drop Controls in WPF WrapPanel

I'm trying to use gong-wpf-dragdrop, couldn't figure out how to implement it. I then follow the following tutorial

http://www.codeproject.com/KB/WPF/gong-wpf-dragdrop.aspx

But when I compile the source code, i开发者_如何学JAVAt throws me a "Output Type of Class Library" error. Can anyone direct me to a good, easy to follow Drag and Drop libraries or tutorial. I'm trying to Drag-Drop-Reorder Controls in a WrapPanel.

Right Click on the SchoolsExample project and select 'Set as Startup Project'