The List Anonymous layout is another layout for the Jms Multi Sites website creation from the front-end.
The website creation from the front-end is a component that allow create or list website.
The List Anonymous is used by the JMS component and there is no JMS module that could be used for that.
The List Anonymous present a list of websites like a directory.
An example can be seen in
www.mywebsite2win.com
If you want to display the list in a module position, this module must be developed.
Something that we have developed but not packaged is a plugin that can be used to do a "Jump to slave site". The idea of this plugin is to be able to add a "combo box" or "drop down list" with the list of all slave site. So that a user can directly jump to the selected slave site.
As this is a plugin that works with a keyword to add in a custom HTML module or in the content of a page, it can be placed anywhere.
It is not yet a product and we can not tell you when we will publich it.
Concerning the second question, it is not clear at all.
I don't understand the http://{site_url}/{rel_site_dir}
The URL of a slave site is not that one. It is in the "domain list".
The {site_url} give the current website URL and the {rel_site_dir} give the location where JMS save the configuration of the slave site and sometime also deploy the slave site itself.