GoJS Samples and VS.NET IDE Design View Editing

Is GoJS sample editing allowed in Visual Studio .NET 2010 Design View?

Is there a way to edit the GUI of the GoJS samples from the VS.NET IDE’s Design View?

I know it can be done from the source code

Yes, that should work – it’s just HTML, after all.
But you do need to write some JavaScript, at least to initialize the Diagram.