In order to workaround this bug, you can handle the OnClientNodeClicking client-side event of the embeddedTree and cancel the propagation of the event if the node that is about to be selected is disabled:

 protected void Page_Load(object sender, EventArgs e)
 {
        Reporting.EmbeddedTree.OnClientNodeClicking = "OnClientNodeClicking";
 }

<script type="text/javascript">
            function OnClientNodeClicking(sender, args) {
                var nodeToSelect = args.get_node();

                if (!nodeToSelect.get_enabled())
                    args.set_cancel(true);
            }
        </script>

Hello,

Our company’s project needs the following functionality:
after dropdown in RadDropDownTree is closed, an event will fire - only ONCE – with all checked nodes.

Currently, NodeCheck event fires immediately for each node checked.
And, onEntryAdded event occurs after the dropdown is closed, but it is fired for each node checked.

Our project involves a lot of data. Therefore, many nodes can be checked by the user. It is unpractical that the event will be fired for each node checked, as this will harm our project’s functionality and performance. 

Thanks,
Daniel.
.Net Programmer at ISR Corp.

All admin fields should have built in label controls.  Several such as RadTextBox do have built in labels and it is not that helpful when some other controls don't have the label functionality.  Makes for a messy page.  Please add in for this and other control types.

The DropDownTree pop-up is not positioned properly when the <form> is wrapped inside a relatively positioned element with fixed width.

The issue can be reproduced with a similar configuration:

    <div style="width: 700px; position: relative; left:300px">
        <form id="form1" runat="server">
            <telerik:RadScriptManager runat="server"></telerik:RadScriptManager>
            <div class="position">
                <telerik:RadDropDownTree runat="server" ID="ddt1" CssClass="dropDownTree"></telerik:RadDropDownTree>
            </div>
        </form>
    </div>

Validation is not working as expected in Dropdowntree. In the demo page http://demos.telerik.com/aspnet-ajax/dropdowntree/examples/validation/defaultcs.aspx, if any one node is checked, the validation message "You need to select a type or a category before submitting the page" is displayed. If multiple checkboxes are checked, the message is not displayed. I do not want the validation message displayed when  check box is  checked.

When I set the RadDropDownTree Enbaled as False, the Clear button still working and clear the Selected value.