Error in VS when trying to drag Gauge to designer area

Feb 24, 2014 at 8:57 PM
Hi Guys,

Just started with WPF. (used WINFORM so far).
I've downloaded the DLL, added it to the toolbox (VS 2012), but when i drag the "Gauge" to the design area i get an error message "a reference was added"WPFGauge..." restart XAML editor...
I've tried to restart the editor, restart VS but nothing.. :/ same error all the time.

Any idea of what i am doing wrong ?