blank sites

Hello,
Re: WordPress 3.1 Multisite root install
I installed and activated your Product theme on my main site, and network activated Gallery and Studio child themes for other user sites. When I go to a user site that is created the site shows as blank. When the user receives an email link to register the main domain/wp-login.php page is also blank. I am not sure what I am doing wrong... The main site displays properly.