There is a missing label in the Box tab (Width and Height options) in the StyleBuilder dialog.

You can dynamically change the label by following this example:

<telerik:RadEditor runat="server" ID="RadEditor1" OnClientCommandExecuted="OnClientCommandExecuted">
    <Tools>
        <telerik:EditorToolGroup>
            <telerik:EditorTool Name="StyleBuilder" />
        </telerik:EditorToolGroup>
    </Tools>
</telerik:RadEditor>

<script>
    function OnClientCommandExecuted(sender, args) {
        var command = args.get_commandName();

        if (command === "StyleBuilder") {
            var dialog = sender.get_dialogOpener()._dialogContainers[command];

            dialog.add_pageLoad(fixSectionName);
        }
    }

    function fixSectionName(sender, args) {
        var dialogWin = sender.get_contentFrame().contentWindow;
        var label = dialogWin.$telerik.$(".reStyleBuilderBoxSize").find("legend");
        label.html("Dimensions");
    }
</script>

RadSpreadSheet control that can open and visualize excel files. It should also support edit and common operations.

For the time being you can use the following workaround:

CSS:
	<style>
		.RadForm_Bootstrap.RadForm.rfdButton form a.rfdSkinnedButton {
			padding: 0px;
			height: 32px;
		}
			.RadForm_Bootstrap.RadForm.rfdButton form a.rfdSkinnedButton input.rfdDecorated {
				height: 32px;
			}
	</style>

ASPX:
		<telerik:RadScriptManager ID="RadScriptManager1" runat="server"></telerik:RadScriptManager>
		<telerik:RadSkinManager ID="RadSkinManager1" runat="server" Skin="Bootstrap" ShowChooser="true"></telerik:RadSkinManager>
		<telerik:RadFormDecorator ID="RadFormDecorator1" runat="server" DecoratedControls="All" />
		<asp:Button ID="Button1" Text="Click" runat="server" />

This leads to possibility for the end-user to press the button before selecting the content area and accept/reject tracked content. 

This can be resolved via some custom code that disables the tools on initial load. For example:

<telerik:RadEditor runat="server" ID="RadEditor1" OnClientLoad="OnClientLoad"
    EnableTrackChanges="true" TrackChangesSettings-CanAcceptTrackChanges="false">
    <Tools>
        <telerik:EditorToolGroup>
            <telerik:EditorTool Name="AcceptTrackChange" Text="Accept Track Change" />
            <telerik:EditorTool Name="RejectTrackChange" Text="Reject Track Change" />
            <telerik:EditorTool Name="AcceptAllTrackChanges" Text="Accept All Track Changes" />
            <telerik:EditorTool Name="RejectAllTrackChanges" Text="Reject All Track Changes" />
            <telerik:EditorTool Name="EnableTrackChangesOverride" Text="Enable Track Changes Override" />
        </telerik:EditorToolGroup>
    </Tools>
</telerik:RadEditor>

<script type="text/javascript">
    function OnClientLoad(sender, args) {
        var editor = sender;
        var toolNamesToDisable = ["AcceptTrackChange", "RejectTrackChange",
            "AcceptAllTrackChanges", "RejectAllTrackChanges"];
        var canAcceptChanges = editor.get_canAcceptTrackChanges();

        if (!canAcceptChanges) {
            for (var i = 0; i < toolNamesToDisable.length; i++) {
                var toolName = toolNamesToDisable[i];
                editor.getToolByName(toolName)
                    .setState(Telerik.Web.UI.Editor.CommandStates.Disabled)
            }
        }
    }
</script>

Using the RadEditor with Auto or Mobile mode in a RadWindow is impossible because JS error are thrown when dialog is shown. 

For the time being, the most proper solution for this case is using the Lightweight mode for RadEditor.

The NuGet packages should not install directories into the project. If these directories are not needed when referencing the dlls traditionally, I can't see why they are needed with the Nuget package. Adding nuget references to ASP.Net AJAX in a non-website/application project results in a silly set of directories. Like, if you want to write a plain assembly that simply uses the Telerik controls in a Server Control.

An install.pl file should handle any web.config alteration on install.

The 

http://demos.telerik.com/aspnet-ajax/editor/mobile-examples/overview/default.aspx

Error: Uncaught TypeError: Cannot read property 'Polling' of undefined

When adding a link with a class name, the Unlink command cannot remove the formatting. 

Temporary solution is to clear anchor's classes programmatically via the ApplyClass command:

<telerik:RadEditor runat="server" ID="RadEditor1" OnClientCommandExecuting="OnClientCommandExecuting">
    <Content>
        <a href="http://www.telerik.com" class="my-class">link</a>
    </Content>
</telerik:RadEditor>

<script type="text/javascript">
    function OnClientCommandExecuting(sender, args) {
        var command = args.get_commandName && args.get_commandName();

        if (command === "Unlink") {
            var myArgs = new Telerik.Web.UI.EditorCommandEventArgs("ApplyClass", null, "");
            sender.fire("ApplyClass", myArgs);
        }
    }
</script>

The dragging clue element is shown before the actual dragging of the element in the Grid is initiated (immediately after the item is clicked). The problem is reproducible in Chrome.

Comment: The problem is not reproducible in the following TreeView demo:
http://demos.telerik.com/aspnet-ajax/treeview/examples/functionality/draganddropnodes/defaultcs.aspx

Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/grid/examples/columns-rows/rows/drag-and-drop/defaultcs.aspx
2. Click over an item (just mouse-down, without moving the mouse nor full click)
Result: The dragging clue is shown without actual moving of the mouse pointer

Cursor is placed in the next available element (e.g., <p>) instead of being placed right after the tab space in the same paragraph.

Possible workaround is to implement a custom command to be triggered with tab key press:

<telerik:RadEditor runat="server" ID="RadEditor1" OnClientLoad="OnClientLoad">
</telerik:RadEditor>

<script>
    Telerik.Web.UI.Editor.CommandList["MyInsertTab"] = function (commandName, editor, oTool) {
        var utils = Telerik.Web.UI.Editor.Utils;
        var selecedElm = editor.getSelectedElement();
        var blockElm = utils.isBlockElement(selecedElm) ? selecedElm : utils.getBlockParent(selecedElm);
        var executeDefaultCommand = utils.isList(blockElm) ||
                                    utils.isTag(blockElm, "LI") ||
                                    utils.isTag(blockElm, "TD") ||
                                    utils.isTag(blockElm, "TH");

        if (executeDefaultCommand) {
            editor.fire("InsertTab");
        } else {
            editor.pasteHtml("<span>&nbsp;&nbsp;&nbsp;&nbsp;</span>&#8203;", commandName);
        }

    };

    function OnClientLoad(editor, args) {
        var shortcutManager = editor.get_shortCutManager();
        // Removing the InsertTabMozilla shortcut will 
        // assure that in Firefox the behavior will be consistent with IE.
        shortcutManager.removeShortCut("InsertTabMozilla");
        editor.addShortCut("MyInsertTab", "TAB");
    }
</script>

Workaround:
<telerik:RadEditor ID="radEditor1" runat="server" EnableTrackChanges="true"
	TrackChangesSettings-CanAcceptTrackChanges="true">
	<Content>
		<table>
			<tbody>
				<tr>
					<td>test</td>
					<td>test</td>
				</tr>
			</tbody>
		</table>
		<p>test paragraph</p>
	</Content>
</telerik:RadEditor>

<script type="text/javascript">
	(function ($T) {
		var prototype = $T.Editor.DefaultToolAdapter.prototype;
		var onContextMenu = prototype.onContextMenu;
		prototype.onContextMenu = function (e) {
			var editor = this.get_editor();
			if (!editor.get_enableTrackChanges()) {
				return onContextMenu.call(this, e);
			}
			if (!this._contextMenusEnabled || editor.get_mode() != $T.EditModes.Design) {
				return;
			}

			this.createContextMenus();
			var element = editor.getSelectedElement() || e.srcElement;
			var contextMenus = this._contextMenus;
			var contextElement = $T.Editor.Utils.getElementParentByCondition(element, function (node) {
				return !!contextMenus[node.nodeName];
			});
			var contextMenuId = contextElement ? contextElement.nodeName : "*";
			var parentTrackChangeEl = $T.Editor.TrackChangesUtils.findTrackChangesParentElement(element);
			if (parentTrackChangeEl) {
				if (parentTrackChangeEl.Type == $T.Editor.TrackChangesElementType.Comment)
					contextMenu = this.createContextMenuWithTrackChangeCommentItems(contextMenuId);
				else
					contextMenu = this.createContextMenuWithTrackChangeItems(contextMenuId);
			}
			else {
				contextMenu = this.createContextMenuWithTrackChangeDefaultItems(contextMenuId) || contextMenus[contextMenuId];
			}
			if (contextMenu) {
				contextMenu.set_eventObject(e);
				contextMenu.show();
			}
			return $telerik.cancelRawEvent(e);
		};
	})(Telerik.Web.UI)
</script>