With the code below I could host an Avalon TextBox in my application, type Python expressions and see the results.  What I still could not do (when I first finished the code) was execute code back in my application.  I needed to give the Python code an object it could make calls on, and I had no examples of doing this.  However, this turned out to be incredibly simple.  On IronPython's PythonEngine class I noticed a method called SetVariable.  It appeared to inject a variable into the Python engine pointing to an object.  I copied the code to my PythonProcessor (you've already seen these lines):

public void SetVariable(string name, object val)

{

Ops.SetAttr(this.Module, name, val);

}

Then, I called this method from my application, passing it the root of my object model:

this.consolePane.Processor.SetVariable("ApplicationManager", this.applicationManager);

A few moments later, I executed ApplicationManager.Version from my console, and I was on my way.  Unfortunately, the application I am working on isn't public, and the hook I am using never will be.  But I can give you a taste of the sort of scripts I can write in Python:

    def createRectangle(self, x, y, brush=Brushes.Red):
        rect = self.createElement(Rectangle)
        undoTransaction = self._viewModel().CreateUndo("CreateRectangle")
        try:
            self.addElement(rect, "Rect")
            rect.Width = 17
            rect.Height = 15
            rect.SetValue(Shape.FillProperty, brush)
            rect.SetValue(Canvas.TopProperty, x)
            rect.SetValue(Canvas.LeftProperty, y)
            undoTransaction.Commit()
        finally:
            undoTransaction.Dispose()
        return rect

These posts should give anyone interested enough to piece together a way of hosting IronPython in their own app.  I'll try to provide a full sample later, but that will have to wait until I have time to write an app, and for newer Avalon bits to go public.