I had a minor frontal shunt and dented the radiator fins against the fan. So far, there is no leakage, but has been told to be on the lookout for sudden coolant leakage. Short of keeping a sharp eye on the temperature gauge, will the check engine light give a warning on an overheating engine?

Cheers.

no it won't it only lets you know if there is something wrong electrically

Most cars nowadays will give u a flashing red light should the coolant temp. rises to the danger zone. Too bad, will have to learn to drive with one eye on the road and the other on the dials then.