Factual error: In 1915 Tolkien was commissioned as a Second Lieutenant with the Lancashire Fusiliers. He (plus various other officers) is constantly shown in the film wearing bright metal cap badge, collar badges and shoulder titles on his Service Dress tunic and greatcoat. However, in the Lancashire Fusiliers officers did not wear shoulder titles on their SD tunics/greatcoats, and their cap/collar badges would have been in a darkened bronze finish, not bright metal (which was for Other Ranks and NCO's).
Factual error: The silhouette elephant weather-vane is incorrectly made and would never point into the wind because the elephants are too far forward.
Factual error: Towards the end of the movie when Superman and Henshaw are fighting on the Watch Tower in space, Lois hits the sun shades to lower them so that direct sunlight can hit Superman and power him up. This is out in space with no atmosphere to filter the sunlight. The reason the blockers were there was for this reason, to keep the harmful unfiltered sun light from hitting people on the ship through the windows. However, she is able to stand there in the direct light after it's done and kiss and hold Superman without being hurt or burned by the intense direct unfiltered sunlight or its radiation.