Not Layout some nodes

What can I do to not layout some shapes. I have a diagram with org chart shapes, but want to add border and title shapes as well. But because I have set the Layout to TreeLayout those shapes will also move in the layout.

How can I disable it for some shapes?

Doing a little search came to the following:

go:Part.LayoutId="{x:Null}" for nodes that should not be moved, am I correct ?

Close, but not quite.

Set go:Part.LayoutId=“None”