One of the stories granddad liked to tell about his childhood actually revolved around that level crossing. Apparently there had been a bank robbery in South London and the get away car was thought to have headed down the Brighton Road, chased by the police. It is hard to believe in these days of the M23, but Crawley High Street WAS the main London to Brighton Road back then! Apparently a message was sent ahead to the local policeman by telegraph. He arranged with the signalman to close the crossing gates, with no train coming, thus blocking the road and apprehending the miscreants.
I have no documentation for this story apart from my own memories of a man who has himself been gone for many years – but I think of it, and of him, whenever I am in Crawley town.