Group is sending email alerts despite settings

We have created a group category that should not send out emails and should require moderation - but neither are happening.

Let me break down our problem to help a bit:

1) We have set the 'Post Moderation' setting for a group to enabled. This means status update posts in this group need to be approved by an admin before being published, and this works. However, the group then automatically sends every group member an email containing the post's text, and a link to it, before it is even approved. This renders the moderation process pointless, as everyone has been sent a copy of the post by email, before it has been moderated. Can we have posts requiring moderation not be sent via email notification before they have been approved?

2) We then attempted to turn off external email notifications for this group by setting the groups Notification setting to 'Internal only'. This doesn't work however. The group still sends both internal and external email notifications when someone makes a post. They get an email no matter what setting we use. The only setting that works is to turn off notifications completely. Can we get the 'internal notification' setting to work again?

3) New discussions posted within the group cannot be moderated. Although status posts require verification, a user can still post discussions at will without moderation. The only way I can see to get around this is to turn discussions off within that group. Is there a way to moderate discussions from within a group?

Thanks for your help!