Clear RedGate Alerts automatically
Once the alert is taken care of, RedGate should send an email saying that the alert is cleared. Also, there is no need of a clear button in the web interface, it should be done automatically.
SQL Monitor lets you configure it to set off another email when an Alert's status has changed to Ended. Would that work for you, or am I misunderstanding your first point?
On your second point; Could you expand on why this should clear automatically?