You can use AD groups as 8MAN users. The process is identical to adding an 8MAN user.
Please note the following:
1.Nested group structures
By default only direct group memberships are considered. If you would like to resolve any nested levels of group membership, please contact support. You will find a howto in our support knowledge base in the article "Use nested groups as an 8MAN user" (support login required). Using complex group structures will increase login time significantly.
2.Hierarchy of role assignments
By using groups, it is possible to assign several roles to a user. In this scenario the login mechanism verifies role columns from left to right and uses the first match. There is no combination of roles.