When Mrs. Benedict unbuttons her blouse to show Sarah the monstrous fetus in her womb, her blouse is completely buttoned back up in the next shot.
In the story about "The Butcher" that takes place in Philadelphia the two police officers in the opening chase have two different badges. The Male is wearing a LA PD badge.
During the first story "the drowned" Edward De LaPoer is tearing the old library books off the shelves, looking for the necronomicon. The books are covered in dust and cobwebs and have clearly not been disturbed for a long time. But their pages are strangely new and and not in the slightest bit yellowed as one would expect for a collection of very old hardbacks.
Bruce Paynes stunt double can be seen when he jumps to the fan above the hotel floor,he slips three times and this can be scene very clearly on the VHS, towards the end of the first story.
Obvious dummy is used for Sam, in the second story, you can clearly see it, and it barely even looks like the actor, this is very obvious from behind to.
In part 2, the setting was around 1970 or early 1971. As the taxi pulls up, yellow dashed road lines are seen on the road. MUTCD introduced these in the summer of 1971, and were rolled out between 1972 and 1974. On the said road, the modern markings would not have appeared for 2-3 years, so therefore should have been white.
All of the stories that are depicted in the Necronomicon that Lovecraft is reading from happen in time periods set after the time period in which his story is set.