Custom notifications with Nagios intregation

I have just enabled Nagios integration which is great for combining multiple emails into 1 ticket, and then auto closing.

I believe it auto closes based on the service/host state mentioned in the emails received.

Can these statuses be used further, for example can we control what Nagios statuses get emailed out, and by extension, can there be an option to only email if a service goes from down (first notification), to critical (second notification).