First, you can verify that the hosting configuration is OK and that the "deployed folder" has the correct value in JMS.
Install the "hello.php" (see tutorial video 7) and execute it on your expected slave site
You should see the domain name and the location on the disk.
When you are sure that the hosting is configured correctly, you can return in JMS and verify the parameters that you used for the slave site.
The domain and the "deploy folder" must be the same as the one displayed by the "hello.php"
A blank page generally mean that you have a PHP Fatal error somewhere.
Check if you have a "error_log" file that perhaps will give you more info on the reason.
We have recently published a new JMS 1.3.30.
See the FAQ for the procedure to get the latest version.
www.jms2win.com/en/faq/faq-joomla-multi-sites#cat-122
We fixed a case on Joomla 3.2 when the "set default language" has a value.
So perhaps that you are in this case and the update will help you.