In the opening scene, Hugo is lying flat on his back, beneath the two cars that have had a head-on collision with one another. But as is shown at the end, Hugo was to be struck from both sides at the same time.
This would have instead shown him wedged between the two, with his upper torso laying on the crushed hoods of both cars.
When Sir Hugo films Clive's death, we see that he's clearly filming from a distance in order to capture a wide shot. However, when Sir Hugo watches the film again with Giles, we see that the film reveals 2 different shots. There's no way Sir Hugo could have filmed a close-up of Clive at that distance.
The two cars that inevitably strike Hugo from opposite sides at the end are driving in the same lane. Making this a disaster already in effect.
Toward the end of the film Robert Powell picks up a glass beaker. It has the Pyrex stamp on it and its volume is stated as 600ml. Victorian England used imperial (non-metric) measures, and Pyrex was not invented until 1915.
The police officer who drags Hugo out from under the two wrecked cars, clearly acted irresponsibly. As a professional officer would know not to disturb the accident scene.