I've been using your plugin on a site that has bbPress installed as well as using the translation ability (i.e. filtering via 'gettext') to rename roles to something more relevant to the client. I've noticed that when displaying roles within AMU that it directly accesses the role_names variable of $wp_roles, and doesn't use the more correct get_editable_roles() or even better wp_dropdown_roles().
Because of directly accessing the role names it ends up showing the bbPress roles (which it shouldn't do since bbPress 2.2 does them differently) and it also doesn't translate the role names of the WP roles.
The relevant lines are as below:
settings.php : lines 197, 202-205
networkoptions.php : lines 340, 347-350, 392-395, 415-418
commonfn.php : lines 26, 110-113
Just thought this might help others.