Alex,
I have a SharePoint group which has a member of an Active Directory group. Permissions for the list are using this SharePoint group and permissions are working as expected. However, when I create a rule where logged in user is in group using the group the rule is not triggered. If I add my individual account to the SharePoint group it works fine. I assume this is a constraint that cannot be avoided? DFFS cannot identify that I am a member of an AD group nested in a SharePoint group?