Hi Will,

The standard way to do this is to create the domain elements and relationships that the shapes and connectors depict. So for example, starting from the "Minimal Language" solution template, you can write things like:

Suppose you add a command to create a new object for each selected object, and a relationship between them. (To see how to create a command, see the examples in Program Files\Visual Studio 2005 SDK\2006.06\VisualStudioIntegration\Samples\DslTools\Example.Customization\Example.ClassDesigner, and look in DslPackage\CtcComponents\ChangeAssociationSort)

internal void OnMenuChangeAssociationSort(object sender, EventArgs e)
{

foreach (object selectedObject in this.CurrentSelection)
{

ExampleElement e1 = object as ExampleElement;
if (e1 == null) continue;

// All updates must be done inside a transaction
using (Transaction t = e1.Store.TransactionManager.BeginTransaction())
{

// create new elements
ExampleElement e2 = new Component(e1.Store);

// add them to the tree
e1.ExampleModel = myModel; // same effect as myModel.Elements.Add(e1)
e2.ExampleModel = myModel;

// add a relationship link
e1.Targets.Add(e2);

t.Commit(); // creates the shapes and connectors and displays them
}
}
}

I haven't tried this myself, but if you take a look at DslPackage\DocData.cs, search on LoadModelAndDiagram. That will give you some hints as to what to do.

You will end up with two modelRoot instances. Your code then needs to decide how to fix that up so that you just have one.

Alan