Another kid’s movie airing in colour on a Saturday morning in the mid to late ’70s on CBC.
The scene I remember has the boy sneaking out of his bedroom late at night and running around a medieval-looking town naked or in his underwear. He finds a bucket or barrel filled with pitch / tar / black paint, dips his hands and feet into it, and jumps up against the wall of the clock tower.
He then gathers a bunch of apples, dips them in the black liquid, and throws them at the top of the tower.
The next morning, the villagers are stunned to find hand and footprints seemingly running up the tower with the clock at the top sporting a sloppy black smiley face.