Unfornately it doesn't ring when silent profile is enabled.
For an Alarm I think it has to ring wether the phone has silent profile selected or General. Because an alarm is there to help you remind something, guess what happens when the normal alarm was silenced when silent profile was active. I would be many times to late :P

And I have to agree with Reinob about point 3. It's a bit incosistent. While the remaining time is visible you expect it continues but instead it starts over again. Stop should immediatly reset the time IMO

Thank you for this wonderful timer