When Antillia steals the boat, the background shows the sea with normal waves. When Demetrios swims out to the boat the water is extremely calm. This also gives away the fact that the shot of Hall swimming was done in a studio tank.
After the rescue of Antilla, Demetrius asks her from where she came. She answers that her land is "beyond the Columns of Hercules". But in time of Atlantis (9000b.C) Hercules hasn't done this job or even has been born (1500 to 1200b.C)
In the House of Fear, a domestic hog appears. Breeders did not start to develop what we know today as the domestic pig until the 18th century of the Christian Era. Before that, domestic swine were almost identical to wild hogs: sharply defined backs, lots of bristly body hair, and very big tusks in their mouths.
Zarin and the priest struggle near the end and the crystal starts shooting randomly. It strikes Zarin and turns him into a skeleton. The skull has the cutting line around it and a metal hook holding it together.