We are going to update our documentation and show how to get the selected text (entries). Until then you could use the following project as a reference. Also you could use the client side events
To save the added entries to the DB you have Entries collection at the server side and you could iterate through it. Regarding to the case to create an entry and check/select a DropDownTreeNode, it is a feature that will be added for the next release.
the Telerik team
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