I just can’t make it work

Is any body there?

It is working just fine. It does not make any changes to your actual site content, only the final html code sent to users and the search engine crawlers.
You can see the external link indicator for Facebook in your sidebar.

Here is that html markup:
<a href="https://www.facebook.com/capeverdeholidays" class="external external_icon" rel="nofollow" target="_blank">Facebook</a>

The external and rel=”nofollow are present.

all is well. nice looking site btw

Hey Mike, I feel a bit of a muppet… thanks for the info, I just didn’t see that is how it works. I am sure you have written it in the plugin description / notes somewhere but I must have missed it. Great plugin! Thanks Philip :o)