Error when trying to delete accordion

In Drupal 8.0.0-dev, I'm trying to delete an accordion item from a user profile. When doing so, I receive an error.

To capture some information about this, I cleared the logs and then attempted to delete the accordion again. The second attached image (and selections) below are what I saw in watch dog.

Type	php
Date	Saturday, October 11, 2014 - 14:45
User	admin
Location	http://192.168.88.88/admin/config/people/accounts/groups/user.user.form.default.group_abt_me/delete?bundle=user
Referrer	http://192.168.88.88/admin/config/people/accounts/form-display
Message	Drupal\Component\Plugin\Exception\PluginNotFoundException: The "" entity type does not exist. in Drupal\Core\Entity\EntityManager->getDefinition() (line 243 of /var/www/drupal/core/lib/Drupal/Core/Entity/EntityManager.php).
Severity	Error
Hostname	192.168.88.1
Operations	

Type	php
Date	Saturday, October 11, 2014 - 14:45
User	admin
Location	http://192.168.88.88/admin/config/people/accounts/groups/user.user.form.default.group_abt_me/delete?bundle=user
Referrer	http://192.168.88.88/admin/config/people/accounts/form-display
Message	Notice: Undefined property: stdClass::$entity_type in Drupal\field_group\Form\FieldGroupDeleteForm->getCancelUrl() (line 84 of /var/www/drupal/modules/field_group/src/Form/FieldGroupDeleteForm.php).
Severity	Notice
Hostname	192.168.88.1
Operations	

Type	php
Date	Saturday, October 11, 2014 - 14:45
User	admin
Location	http://192.168.88.88/admin/config/people/accounts/groups/user.user.form.default.group_abt_me/delete?bundle=user
Referrer	http://192.168.88.88/admin/config/people/accounts/form-display
Message	Notice: Undefined property: stdClass::$label in Drupal\field_group\Form\FieldGroupDeleteForm->getQuestion() (line 69 of /var/www/drupal/modules/field_group/src/Form/FieldGroupDeleteForm.php).
Severity	Notice
Hostname	192.168.88.1
Operations	

Other potentially useful information.

This is a vagrant dev environment form from https://github.com/geerlingguy/drupal-dev-vm.

$ php -v
PHP 5.4.33-2+deb.sury.org~precise+1 (cli) (built: Sep 25 2014 09:06:25) 
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies

$ uname -a
Linux precise64 3.2.0-23-generic #36-Ubuntu SMP Tue Apr 10 20:39:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

$ drush status
 Drupal version         :  8.0.0-dev                                            
 Site URI               :  http://default                                       
 Database driver        :  mysql                                                
 Database hostname      :  localhost                                            
 Database port          :                                                       
 Database username      :  root                                                 
 Database name          :  drupal                                               
 Database               :  Connected                                            
 Drupal bootstrap       :  Successful                                           
 Drupal user            :  Anonymous                                            
 Default theme          :  bartik                                               
 Administration theme   :  seven                                                
 PHP executable         :  /usr/bin/php                                         
 PHP configuration      :  /etc/php5/cli/php.ini                                
 PHP OS                 :  Linux                                                
 Drush version          :  7.0-dev                                              
 Drush temp directory   :  /tmp                                                 
 Drush configuration    :                                                       
 Drush alias files      :                                                       
 Drupal root            :  /var/www/drupal                                      
 Site path              :  sites/default                                        
 File directory path    :  sites/default/files                                  
 Temporary file         :  /tmp                                                 
 directory path