I have the multisites component setup and patches installed (master site: pangborn-eu.preview.interworks.com). I'm trying to setup my first slave site (vogelandschemmann.preview.interworks.com). When I get to the end of the installation script, it gives me the textarea with the configuration.php code in it, which leads me to believe I have some permissions problems. I manually saved the configuration.php file to the subdirectory that multisites created (/multisites/vogelandschemmann), but when I try to go to the new slave site I get the first step of Joomla installation (select language) again. I have the hello.php file copied to the master site if that helps any. Can you please point me in the right direction? I think your component will be exactly what I need once I get past this hurdle. Thanks in advance.

You have to save the "configuration.php" into the "deploy directory" that may be different of the "/multisites/{site_id}

How do I determine where the deploy directory is? Does a different deploy directory get created for each slave site?

Deploy direectory is the parameter that you have specified in JMS "manage site".
Review the tutorial video CP-04 that show how to configure a slave site into a specific directory.
www.jms2win.com/tutorial#jms12x-CP-04