After a test run, I don't think this will work for me...
because of the jos_ thing, my database was wiped out.
I restored the backup files in my database, then uninstalled the component.

Now, when I try to install anything else, I am told that I can't unless I'm working on the master site. I don't have a master site anymore.

What other little goodies need to be removed?


* This extension is not found in the master site.
* Please install it first in the master site before installing it into the slave site
* Install Component Error



I would prefer not to have to rebuild the entire site.

When you create a slave site, if you give exactly the same DB and the same table prefix than your master website, this is equivalent to install another joomla with using an existing DB and existing prefix. So this will delete your current website and the "bak" table will be used.

If you have created the slave site with another table prefix (see the "users manual" and "demo installation" document if you don't know how to do that), then the installation of extensions must be installed on the master site before it is installed on a slave sites.
The reason is that it re-install the files and folders on the disk.
This explain why JMS require that you install the extension on the master first.

Okay... where's my master site?
Because I was using a DB that used the jos_ prefix, when I attempted to add a slave site, it killed the master. I got it back by restoring from the backup. I then uninstalled the component, and tried to install something else, but I still get the install failure because of a no-longer-existing 'master/slave' deal.

JMS does not perform DB access.
JMS only modify files of Joomla to allow using multiple configuration.
In your case, it seems that you have created a slave site with the standard Joomla Installation and that your have used the same DB and the SAME table prefix than your master. In this case, the Joomla Installation copy the table into bak_.
This is the standard Joomla Installation procedure.
So if you want to recover the tables, you have to recover the bak_ table and restore them with the table prefix they have before (probably jos_)