Hi there,
I am sorry for the inconvenience caused. Currently, we're in the midst of updating our documentation. It will be available soon.
But in the mean time, let me assist you with the issues in hand. Are you referring to this:
http://take.ms/lXQc5 and
http://take.ms/o6OYl . This is actually a module which was installed together with the Vanilla template. It should be enabled by default. However, if it didn't you can actually enable it yourself from backend.
Navigate to your Joomla backend > Extensions > Module . Locate this module "Vanilla Sidebar Module" and make sure it is enabled:
http://take.ms/Y5Hgv . If there is none, you can add it by clicking on New button.
Regarding your second question, you can turn on "Preview Module Position" from your Joomla setting. Navigate to System > Global Configuration > Templates.
http://take.ms/b2D5u . Once you have turn on this, you can view the available module position on your site by appending ?tp=1 on your url. Example:
http://vanilla.stackideas.com/?tp=1
Hope this helps.
P/S: In the future, please start a new ticket for any new questions rather than posting on your existing thread as it would be more difficult for us to manage in the future.