Hi!
Willr, there's something broken in this part of the forum (v0.2.0), at least under SS 2.3.1. You can not assign roles to members. Also, in the Access tab of forums, there's a 'Who can post to the forum?' radio box with four choices that's not working well: there's no text to explain the choices, and only the third an fourth of them triggers a drop-down box for selecting Security groups.
Best regards,
Juan