Thanks. I did actually have it displaying in a tool window, but I wasn't sure how to associate a toolbox with a particular diagram.
So I have a 'Main' window, which has a RadDock and some tool windows, and I had a RadForm per diagram, with its own toolbox dropped on the form. Now I realize that's bad, and my Diagram 'container' form needs to have its own RadDock, and a Document window for each form (which contains a RadDiagram). That way the one toolbox will work for every diagram.
Is my last statement correct? Thanks.