application-loading works

application-loading.template.hbs

<div class="loading">
	<h2> Things are slow </h2>
</div>

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle'
});

application.route.js

import Ember from 'ember';

export default Ember.Route.extend({
  model(){
    		return new Ember.RSVP.Promise(function (resolve) {
          
			Ember.run.later(function () {
				resolve({name: 'bob', id: 1});
			}, 5000);
		});
  }
});

application.template.hbs

<div class="application">
  <h1>application-loading works</h1>
  <h4>when the application route is the slow route, the application-loading template works.</h4>
  <br>
  <br>
  <p>{{model.name}} is the model </p>
  <br>
  <br>
</div>

styles.app.css

body {
  margin: 12px 16px;
  height: 100%;
  width: 100%;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  font-size: 12pt;
}

.loading {
  background-color: #EEF; 
	min-height: 200px;
}

.application {
	background-color: #EFE;
  min-height: 400px;
}

twiddle.json

{
  "version": "0.4.10",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/1.13.11/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember-template-compiler.js"
  }
}