diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
index b2a94b0..3dd0b0a 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
@@ -470,11 +470,11 @@ public function importChange($name, Config $new_config, Config $old_config) {
     $entity->original = clone $entity;
 
     foreach ($old_config->get() as $property => $value) {
-      $entity->original->$property = $value;
+      $entity->original->set($property, $value);
     }
 
     foreach ($new_config->get() as $property => $value) {
-      $entity->$property = $value;
+      $entity->set($property, $value);
     }
 
     $entity->save();
diff --git a/core/modules/config/lib/Drupal/config/Tests/ConfigEntityListTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityListTest.php
index f19c03d..1eacd3b 100644
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigEntityListTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityListTest.php
@@ -43,10 +43,10 @@ function testList() {
 
     // Get a list of ConfigTest entities and confirm that it contains the
     // ConfigTest entity provided by the config_test module.
-    // @see config_test.dynamic.default.yml
+    // @see config_test.dynamic.test.config.yml
     $list = $controller->load();
     $this->assertEqual(count($list), 1, '1 ConfigTest entity found.');
-    $entity = $list['default'];
+    $entity = $list['test.config'];
     $this->assertTrue(!empty($entity), '"Default" ConfigTest entity ID found.');
     $this->assertTrue($entity instanceof ConfigTest, '"Default" ConfigTest entity is an instance of ConfigTest.');
 
@@ -55,13 +55,13 @@ function testList() {
     $expected_operations = array(
       'edit' => array (
         'title' => 'Edit',
-        'href' => 'admin/structure/config_test/manage/default/edit',
+        'href' => 'admin/structure/config_test/manage/test.config/edit',
         'options' => $uri['options'],
         'weight' => 10,
       ),
       'delete' => array (
         'title' => 'Delete',
-        'href' => 'admin/structure/config_test/manage/default/delete',
+        'href' => 'admin/structure/config_test/manage/test.config/delete',
         'options' => $uri['options'],
         'weight' => 100,
       ),
@@ -82,7 +82,7 @@ function testList() {
     $build_operations = $controller->buildOperations($entity);
     $expected_items = array(
       'label' => 'Default',
-      'id' => 'default',
+      'id' => 'test.config',
       'operations' => array(
         'data' => $build_operations,
       ),
@@ -126,7 +126,7 @@ function testListUI() {
     // the second contains the machine name, and the third contains the
     // operations list.
     $this->assertIdentical((string) $elements[0], 'Default');
-    $this->assertIdentical((string) $elements[1], 'default');
+    $this->assertIdentical((string) $elements[1], 'test.config');
     $this->assertTrue($elements[2]->children()->xpath('//ul'), 'Operations list found.');
 
     // Add a new entity using the operations link.
@@ -177,7 +177,7 @@ function testListUI() {
     // Verify that the text of the label and machine name does not appear in
     // the list (though it may appear elsewhere on the page).
     $this->assertNoFieldByXpath('//td', 'Default', "No label found for deleted 'Default' entity.");
-    $this->assertNoFieldByXpath('//td', 'default', "No machine name found for deleted 'Default' entity.");
+    $this->assertNoFieldByXpath('//td', 'test.config', "No machine name found for deleted 'Default' entity.");
 
     // Confirm that the empty text is displayed.
     $this->assertText('There is no Test configuration yet.');
diff --git a/core/modules/config/lib/Drupal/config/Tests/ConfigImportTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigImportTest.php
index 95089f7..d06acc8 100644
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigImportTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigImportTest.php
@@ -43,11 +43,11 @@ function setUp() {
    * Tests omission of module APIs for bare configuration operations.
    */
   function testNoImport() {
-    $dynamic_name = 'config_test.dynamic.default';
+    $dynamic_name = 'config_test.dynamic.test.config';
 
     // Verify the default configuration values exist.
     $config = config($dynamic_name);
-    $this->assertIdentical($config->get('id'), 'default');
+    $this->assertIdentical($config->get('id'), 'test.config');
 
     // Verify that a bare config() does not involve module APIs.
     $this->assertFalse(isset($GLOBALS['hook_config_test']));
@@ -57,13 +57,13 @@ function testNoImport() {
    * Tests deletion of configuration during import.
    */
   function testDeleted() {
-    $dynamic_name = 'config_test.dynamic.default';
+    $dynamic_name = 'config_test.dynamic.test.config';
     $storage = $this->container->get('config.storage');
     $staging = $this->container->get('config.storage.staging');
 
     // Verify the default configuration values exist.
     $config = config($dynamic_name);
-    $this->assertIdentical($config->get('id'), 'default');
+    $this->assertIdentical($config->get('id'), 'test.config');
 
     // Create an empty manifest to delete the configuration object.
     $staging->write('manifest.config_test.dynamic', array());
@@ -108,6 +108,7 @@ function testNew() {
       'label' => 'New',
       'style' => '',
       'langcode' => 'und',
+      'description' => '',
     );
     $staging->write($dynamic_name, $original_dynamic_data);
 
@@ -142,7 +143,7 @@ function testNew() {
    */
   function testUpdated() {
     $name = 'config_test.system';
-    $dynamic_name = 'config_test.dynamic.default';
+    $dynamic_name = 'config_test.dynamic.test.config';
     $storage = $this->container->get('config.storage');
     $staging = $this->container->get('config.storage.staging');
 
diff --git a/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php
index dd24224..40d498e 100644
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php
@@ -60,6 +60,7 @@ function testImport() {
       'label' => 'New',
       'style' => '',
       'langcode' => 'und',
+      'description' => '',
     );
     $staging->write($dynamic_name, $original_dynamic_data);
 
@@ -128,4 +129,22 @@ function prepareSiteNameUpdate($new_site_name) {
     $config_data['name'] = $new_site_name;
     $staging->write('system.site', $config_data);
   }
+
+  /**
+   * Tests updating existing configuration.
+   */
+  public function testUpdate() {
+    // Create a staged version of the configuration object with different data.
+    $config_data = config('config_test.dynamic.test.config')->get();
+    $config_data['description'] = $this->randomName();
+    $this->container->get('config.storage.staging')->write('config_test.dynamic.test.config', $config_data);
+
+    $this->drupalGet('admin/config/development/sync');
+    $this->drupalPost(NULL, array(), t('Import all'));
+    $this->assertText(t('There is no configuration to import.'));
+
+    $entity = entity_load('config_test', 'test.config');
+    $this->assertIdentical($entity->get('description'), $config_data['description']);
+  }
+
 }
diff --git a/core/modules/config/lib/Drupal/config/Tests/ConfigInstallTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallTest.php
index b549119..ff57878 100644
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigInstallTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigInstallTest.php
@@ -34,7 +34,7 @@ function setUp() {
    */
   function testModuleInstallation() {
     $default_config = 'config_test.system';
-    $default_configuration_entity = 'config_test.dynamic.default';
+    $default_configuration_entity = 'config_test.dynamic.test.config';
 
     // Verify that default module config does not exist before installation yet.
     $config = config($default_config);
diff --git a/core/modules/config/tests/config_test/config/config_test.dynamic.default.yml b/core/modules/config/tests/config_test/config/config_test.dynamic.default.yml
deleted file mode 100644
index 3e50e3b..0000000
--- a/core/modules/config/tests/config_test/config/config_test.dynamic.default.yml
+++ /dev/null
@@ -1,2 +0,0 @@
-id: default
-label: Default
diff --git a/core/modules/config/tests/config_test/config/config_test.dynamic.test.config.yml b/core/modules/config/tests/config_test/config/config_test.dynamic.test.config.yml
new file mode 100644
index 0000000..6917b1f
--- /dev/null
+++ b/core/modules/config/tests/config_test/config/config_test.dynamic.test.config.yml
@@ -0,0 +1,3 @@
+id: test.config
+label: Default
+description: Default
diff --git a/core/modules/config/tests/config_test/lib/Drupal/config_test/Plugin/Core/Entity/ConfigTest.php b/core/modules/config/tests/config_test/lib/Drupal/config_test/Plugin/Core/Entity/ConfigTest.php
index 52da777..c99ecc2 100644
--- a/core/modules/config/tests/config_test/lib/Drupal/config_test/Plugin/Core/Entity/ConfigTest.php
+++ b/core/modules/config/tests/config_test/lib/Drupal/config_test/Plugin/Core/Entity/ConfigTest.php
@@ -62,4 +62,25 @@ class ConfigTest extends ConfigEntityBase {
    */
   public $style;
 
+  /**
+   * The description for the configuration entity.
+   *
+   * @var string
+   */
+  protected $description;
+
+  /**
+   * Overrides \Drupal\Core\Config\Entity\ConfigEntityBase::getExportProperties();
+   */
+  public function getExportProperties() {
+    $properties = parent::getExportProperties();
+    $protected_names = array(
+      'description',
+    );
+    foreach ($protected_names as $name) {
+      $properties[$name] = $this->get($name);
+    }
+    return $properties;
+  }
+
 }