I want my slave site to have its own robots.txt independent of my master website.
I tried follow the instructions on this forum thread => www.jms2win.com/en/forum/24-joomla-multi...r-different-websites

But so, far unsuccessful in having separated robots.txt, even that the template accepts the modification the slave site still pointing to the master sites's robots.txt.

Any idea hot to fix it?

//master site
sohounix.com/robots.txt

//slave site
rosewooddental.com/robots.txt

Appreciated!

The link that you provided is correct and the procedure is correct.

Let me re-explained otherwise.
If you already have create the "robot.txt" into the slave site, you first need to remove it (delete it).
Change the JMS Template rule that you used to build your slave site.
To know the JMS template rule name, go in Manage site and edit your slave site.
This is the field "template" that give the name.

Go in JMS Template site and edit the template.
Go in the "file and folder" tabs and modify the action for the "robots.txt" and replace the "symbolic link" by "copy".

Return in the "manage site" and edit the slave site and re-save it.
This will detect that the "robots.txt" is not present and will use the action "copy" to rebuild it (instead of the symbolic link)