Volunteer Registration Application

Hi I have created a account in Volunteer Registration App available on Marketplace. When I add a volunteer to the list, the app sends a email to me(admin) and the person who has been added as a volunteer. The email also includes a link to view/edit the details of the person added. Unfortunately the link does not works. I can see the scripts in Send email are incorrect, but I am not sure how to correct them. Could you please help me Thanks