I purchased the bundle for this site and attempted to put in Site Offline mode and it will not do so.

I thought it may have something to do with this "NoNumber Cache Cleaner" However, it's unclear the importance of this plugin for this template.

Any help on either a fix or workaround to this issue?

Hello Alan,

Please check if your configuration.php is writable.
It needs to be if you want to put your site in offline mode.

You can always force it by changing the following line
public $offline = '1';

(Just change 0 top 1)

Just as an FYI, the resolution to this problem was to go and make sure all the permissions were set properly in the Permissions Tab of the Global Configuration area. They all needed to be set to "not set". This is not to say permissions cannot be modified, it's just that I needed to set those, possibly a conflict with ACL or ACL Manager component.

Thank you Alan.