Maintenance & Coming Soon Extension
Here is how the "Maintenance & Coming Soon" extension works :
First, you'll need to activate it :
This will give you access to an options page "Settings" link (it'll show up when you click the activate button).
(Note: When you click on the button, it will automatically creates a page named "maintenance". Please don't edit it, the name doesn't matter, as the content.. All need to be filled in the Extension's settings. Moreover, that page will be deleted when you deactivate the extension.)
Secondly, the Settings :
Really easy, nothing more...
Let us know if you have any question.