No, everything is hardcoded to work with 'num' as the unique identifier.  Depending on your use case you might be able to add an id field and keep them updated or in sync.  It would take some experimenting though.

I'll give it a try.

We haven't tested that but if you're comfortable modifying the code you could try disabling the error checking in /lib/admin_functions.php in the installIfNeeded() function

    //if     (!$_REQUEST['mysqlTablePrefix'])                          { alert("Please enter your 'MySQL Table Prefix'<br>\n"); }
    //elseif (preg_match("/[A-Z]/", $_REQUEST['mysqlTablePrefix']))    { alert("Value for 'MySQL Table Prefix' must be lowercase.<br>\n"); }
    //elseif (!preg_match("/^[a-z]/i", $_REQUEST['mysqlTablePrefix'])) { alert("Value for 'MySQL Table Prefix' must start with a letter.<br>\n"); }
    //elseif (!preg_match("/_$/", $_REQUEST['mysqlTablePrefix']))      { alert("Value for 'MySQL Table Prefix' must end in underscore.<br>\n"); }
    //elseif (preg_match("/[^a-z0-9\_\-\.]/i", $_REQUEST['mysqlTablePrefix'])) { alert("Please enter a valid 'MySQL Table Prefix' (Example: cms_)<br>\n"); }

And then deleting/renaming /data/isInstalled.php to get back to the install screen.

Maybe do a full backup first and then try to restore.

Hope that helps!

Can I install or remove the MySQL prefix of the cmsBuilder (so I can merge later with another project).

regards,
Karls