Hello! 

You may check details about settings for Migration Tool here https://github.com/unaio/una/wiki/Dolphin-Migration-Tool

About migration tool path:

The simplest way to find the path is to open inc/header.php file of your Dolphin script (which is located on the same server as UNA) and copy $dir['root'] value, then put it to Define path to the root Dolphin's folder text box and save, then you will see the list of the available for trasnfer content in table below.