Using PrivateMSG Roles

Hello, we are currently trying to use the privateMsg_Roles Module (included with privateMsg) to enable our users to send Messages to all users, to all teachers etc. I've personally used this module in another Drupal Project before and it worked quite seemlesly. In Opigno however I can't get the user roles to show up in the Receipient List and therefor I cannot send Messages to a Role. I've looked into the code for a bit but I couldn't find anything that looked like it's causing this. I thought it might be a problem with one of the platon templates. Has anyone ever had this problem or does anyone have an Idea on how to fix this? Sincerely, Justus Schneider