I have a Development joomla install that is used for testing prior to install, editing or changing our Master. They are identical in versions, components, modules, and plugins. I installed a new component to test. I did so without any issues/problems.

Then, I have a Master site with multiple Slave sites. To this point, all the components/modules/plugins installed on the Master are being used by all Slave sites.

I recently installed a new component, that is only going to be used on a single Slave site. I installed that component on the Master site.

Afterwards, my Slave sites needed to be resync'd. I resync'd all Slave sites. After resync'ing the Slave sites. When looking at any of the Slaves, I noticed that some of the content had reverted to the state of when first launching a Slave from the Master. This included some written content, menus, modules, images, etc.

I then took the backup Files & DB for each Slave site and restored them. This only included the unique Files/Folders & DB for each Slave. Now each Slave was displaying correctly (written content, menus, modules, images, etc).

Now I began to setup and configure the new component on the single Slave. The first thing I noticed was the component was not showing in the back-end (admin) menu. I had to insert the correct table rows into #_extensions and #_menu. After doing so, the component was listed in the back-end (Admin) menu.

Continuing with the setup and config, the rest went smoothly. After I began to do testing via the front-end, I started to notice a number of styling changes and files that are linked correctly that no longer work.

I am at a loss as to the issue. Both my Development and Master/Slaves are using the same css files, the files and folders seem to be identical and the DB table seem to be identical. Yet, I am experiencing different behavior in the two environments.

I am thinking I may have overlooked something important when resync'ing my Slaves.

I would like to better understand the process for installing new components, modules and plugins, to resync'ing the Slaves while maintaining each Slaves unique content.

If I can clarify anything for you or I need to purchase more support time, please let me know. Thanks.

Based on what I understand, you have a master and several slave sites that are children (derived) from the master.
That would explain why you had the "resync" icon to tell you that some table exists in the master and not in the slave sites.
When you the "refresh" icon, you can use the JMS Tool menu to see which MySQL table were added or missing.

When you just need to install a new extension in a slave site that does not need to be present in the other slave site, you just have to:
- Either use the JMS tool menu to re-install the extension in the specific slave site
- OR go in the back-end of the slave site to re-install the extension
- OR go in the back-end of the slave site to do discover and install.

When you open/resave a slave site definition, JMS verify that each "top" files and folders on the disk are present and when not present, apply the action defined in the JMS template rule.
It does the same with the DB and check if all the tables are present or not.
When not present, it perform a copy or a sharing depending on the JMS template (sharing) rules.