To better explain the question, I have this example:
I have this node (/content/data/marketo/events) of type nt:folder. In CRXDE if I create a new node of type nt:unstructured inside the events folder, I would get an error.
nt:folder: This node type represents a plain file system folder (it can have nt:folder and nt:file children and only a few restricted meta data properties) // so quite restricted in terms of properties and nodes.