Both of the points you have made seem to be issues. It sounds logical to have these by default. I will contact our development team and will inform them about the matter.
The workaround to the first issue you have already implemented. As for the second, it would be hard to determine that the Node is being dragged below or above another Node only by using the client side API of the TreeView.
Thank you for paying attention to these issues and letting us know about them. I will follow up in this thread with additional information as soon as I have it.
the Telerik team
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