wxTreeCtrl InsertItem Method

Good Day All:

I'd like to use the wxTreeCtrl InsertItem method.

1.   I tried calling it and got a loading error which unfortunately I
didn't copy down the exact wording. Is this method wrapped?

2.    Also, to insert an Item, you need an empty Item to insert.

I found wxTreeItemId in wxCore, but the comment says it's not intended to
be constructed explicitly by the user. How should you make an empty Item?

AppendItem works as advertised, but the node is appended after the last
child node which is not exactly what I'd like to do. It could be dragged
where needed, but that adds another step.

Ideas?
Thanks,
James