While we don't have video tutorials for every feature on the configuration page our documentation is pretty good. If you click on the blue question mark within the settings page it should take you to the documentation page that covers that specific area.
In terms of the pool links, you can add as many manual links as you want. You also need to set the number you would like to inject into the back button stack. If you added 3 links, and said to inject 2 into the stack, it would either pick the first two from the bottom up if you did not have the random box checked, or if you had random checked it would randomly pick 2 links to inject. Alternatively, if you put 3 manual links and said to inject 5 links into the back button, it would pick randomly from the 3 and place them into the back button stack 5 times.
If you do put zero, then yes it will just use the final lookup link which you can also control how many times it goes into the back button stack.
