Other mistake: When the throne in episode 5 & 6 is first introduced it is a normal throne or chair; it doesn't move when merely touched. But once the ceremony starts and after it's finished, it's suddenly a swivel chair. The base is never shown of course. But a swivel chair made of solid rock...?
On the Track - S1-E6
Continuity mistake: Todd Edwards' car throughout the series is an Austin Maxi, but when it rolls down the bank, it has changed into an Austin 1800.