NUnit Gui questions: How to output messages to the Console.Out or Trace Output tabs

Hi,

How do I output messages to the Trace Output tab?  Also, what is the difference between "Trace Output" and "Internal Trace"?  What is the "Console.Error" tab used for.  I suspect to view errors but isn't that what the Assert....() is used for?

For example, I have something like this in my test:

Trace.WriteLine("trace line");
Debug.WriteLine("debug line");

but neither shows up in the NUnit Gui.

Thanks