Difference Between TMDG movie and acutal TMDG story

The were other guests in Zaroff's house. Such as the drunk man and the lady, also when the story mentioned that he heard a MONSTER screaming, in the movie it was a man or woman screaming. Also they did not call Zaroff, "General" Zaroff like in the story, but Count Zaroff. The story also did not mention that General Zaroff had other servants, and also there weren't any Captains or friends on the ship; as shown in the movie. There was also no Whitney in the story, but rather four other people. Also, it wasn't like the story, where Rainsford fell off the ship to get his pipe, but it was rather the ship crashed. Also, it did not mention anything about sharks in the water.