Mocking a Configuration Section

Hello,

In .NET, I created a custom configuration section that I want to mock. In my configuration section, I return an instance of the configuration section through the Instance property (a static property), which calls ConfigurationManager.GetSection("mySection") to get a reference to the section. So I have code that checks to see if MySection.Instance != null, then if not null, access the child properties of the section, like:
if (MySection.Instance.SomeProp != null)
return MySection.Instance.SomeProp;
else
return null;

How much with custom configurations can I override with TypeMock, and how? Has anyone tried?