Evan is supposed to be checking on the alternate email issue.
If someone wants to leave a community, they can't add themselves back in. However, the system will readd them anyway. If you are in a security group, you will automatically be added to the communities for that security group. So we probably need to set each community to not allow them to leave. We are talking about having a different security group for Sage 300 so we can get just the people who want to be in it, in it.