as specified, the activities linking is not incorporated in the Moodle main distribution. ( it works well but the teacher interface is nearly inexistant, the installation process is a little bit hard, the code is not speed optimized nor Martinized
That is why you should try it on a test server with the same softwares ( Moodle, php, mysql, .. ) and database content as your production server. That way you will understand clearly it installation procedure and it functionnality. And you will have all the first hand ( yours hands
Have a good testing,
Bernard