Other mistake: Shortly after David and Griffin jump to Japan, Griffin goes to a car dealership and takes a Mercedes. The car should have its steering on the right side of the car but it's on the left. Griffin is also driving on the right side of the street rather than on the left.
Continuity mistake: In the scene where David jumps to a glacier and is hit head-on with a pick-up by Griffin, they then jump into the middle of a guerilla war. The pick-up crashes and a driver is seen at the wheel beside Griffin. The shot changes to wider and when Griffin is seen exiting the car, the driver has disappeared. (01:12:30)
Continuity mistake: The lead character wears a grey waffle crew neck shirt. It gets wet and has obvious and poorly executed water spots for way too long after they jump to Tokyo. Then when he is jumping back and forth, three huge holes appear and disappear in the next jump, and the breakdown on the costume goes from heavy to none to medium. It looks like they edited sequences out of the order in which they shot them, because no wardrobe mistress could make such huge errors.
Continuity mistake: In the coliseum, Griffin breaks off the hand of a statue with his bat then picks it up and holds it in his right hand while the bat is in his left. When he jumps backwards, the bat is in his right hand but the statue's hand is gone. Griffin jumps in front of David and throws the statue's hand from his right hand and switches the bat from his left hand to his right.
Continuity mistake: Considering the speed and direction the cab was travelling at when they pull up in the Colosseum parking lot, there doesn't appear to be a reasonable point of entry. Following the scene, it seems as if the cab must have driven over a grass verge and through a group of tourists.
Audio problem: In the scene when he goes back to his home and finds his dad on the floor, he walks into the house and you can see Family Guy playing on the tv and hear it very quietly. Unfortuanately, the audio is coming from a completely different scene in the episode than the video. (You can see Lois is in the zoo, which comes from the beginning of the episode, yet the conversation you can hear is when they are sat in the kitchen towards the end of the episode.)
Visible crew/equipment: After they enter the Colosseum in Rome, you get a wide shot of the Colosseum. On the left you see two guys: one is standing behind what appears to be a camera, and the other one is crouching.
Continuity mistake: David's yellow backpack disappears right before he falls on the frozen lake. He was wearing it just a second before, when he showed the snow globe. (00:03:20)