I am trying to build a new section in Umbraco 7.6.

I had this working the 'old' way that use the tree controller extending from BaseTree but it was very ugly.

I'm now trying to do it using TreeController. I have followed the tutorials by:

1. Kevin Giszewski (https://github.com/kgiszewski/LearnUmbraco7/blob/master/Chapter%2016%20-%20Custom%20Sections%2C%20Trees%20and%20Actions/01%20-%20Create%20a%20Section.md)

2. and another by Tim Geyssens (https://github.com/TimGeyssens/UmbracoAngularBackofficePages)

but all I'm getting is an empty section without the tree and just with the title:

The controllers are not even hit on debugging, no console errors, no 500 errors, all compiles fine too.

Here's my code:

trees.config:

<add initialize="true" sortOrder="0" alias="UmbracoBookshelfTree" application="UmbracoBookshelf" title="Umbraco Bookshelf" iconClosed="icon-folder"
    iconOpen="icon-folder-open" type="UmbracoBookshelf.Controllers.UmbracoBookshelfTreeController, MyWebsite.Backoffice"/>

applications.config:

<add alias="UmbracoBookshelf" name="Umbraco Bookshelf" icon="icon-globe-inverted-america" sortOrder="5"/>

Section:

using umbraco.businesslogic;
using umbraco.interfaces;

namespace UmbracoBookshelf.Applications
{
    [Application("UmbracoBookshelf", "Umbraco Bookshelf", "icon-globe-inverted-america", 5)]
    public class UmbracoBookshelfApplication : IApplication
    {
    }
}

Tree controller:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http.Formatting;
using System.Web;
using umbraco;
using umbraco.BusinessLogic.Actions;
using Umbraco.Core;
using Umbraco.Web.Models.Trees;
using Umbraco.Web.Mvc;
using Umbraco.Web.Trees;

namespace UmbracoBookshelf.Controllers
{
    [PluginController("UmbracoBookshelf")]
    [Umbraco.Web.Trees.Tree("UmbracoBookshelf", "UmbracoBookshelfTree", "Umbraco Bookshelf", iconClosed: "icon-folder")]
    public class UmbracoBookshelfTreeController : TreeController
    {

        protected override Umbraco.Web.Models.Trees.MenuItemCollection GetMenuForNode(string id, System.Net.Http.Formatting.FormDataCollection queryStrings)
        {
            var menu = new MenuItemCollection();

            if (id == Constants.System.Root.ToInvariantString())
            {
                // root actions              
                menu.Items.Add<CreateChildEntity, ActionNew>(ui.Text("actions", ActionNew.Instance.Alias));
                menu.Items.Add<RefreshNode, ActionRefresh>(ui.Text("actions", ActionRefresh.Instance.Alias), true);
                return menu;
            }
            else
            {
                //menu.DefaultMenuAlias = ActionDelete.Instance.Alias;
                menu.Items.Add<ActionDelete>(ui.Text("actions", ActionDelete.Instance.Alias));

            }
            return menu;
        }

        protected override TreeNodeCollection GetTreeNodes(string id, FormDataCollection queryStrings)
        {
            var nodes = new TreeNodeCollection();

            nodes.Add(CreateTreeNode("123", "456", queryStrings, "Some name to be shown"));
            nodes.Add(CreateTreeNode("789", "456", queryStrings, "Some other name to be shown"));

            return nodes;
        }
    }
}

It's pretty simple, what could wrong here?