Software » Web » Redmine plugins » Scrum

Hi, I'm new to redmine and this scrum plug-in, and am investigating its potential to use in a software engineering course I teach. I'm currently trying to figure out how to link revisions in the repository to project issues. I see in the pages online here that some issues have an "Associated Revisions" panel with links to the code. Would someone please tell me how to create these links? Also, are there any tutorials / videos or webpages available for this scrum plug-in?

Thanks!