I entered 1,3,5 - Unregistered / Not Logged In, Users Awaiting Email Confirmation and (COPPA) Users Awaiting Moderation - but as it turns out, if you're not logged in, you can't post anyway, so does this come under the classification of a conflict issue?
[EDIT]Found it, must be an issue with the setting for the options, you can only set it to 'Can view shoutbox and messages' or 'Cannot view shoutbox' - the last one 'Can view shoutbox, but not messages' throws back the error ... works fine now after changing from that option

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