Dipper, Mable, Soos, Wendy and McGucket gather around each other to discuss a plan to save Ford. We then see a cut to a close-up of Stan, with Wendy suddenly in the background.
When the wheel is destroyed by Bill, Soos is to the right of Dipper and Mabel but when the camera shows a close-up of them, Soos is behind them.
When Bill is confronting everyone before he destroys the Zodiac, the wheel is missing from the floor.
Before Bill destroys the circle, Ford is to the left of Stan, but when the camera jumps to an overview they have switched places.
Before Bill destroys the Zodiac wheel, Pacifica and Soos can be seen behind Stan and Ford, but when the camera shifts to the circle as it is burned, Mabel and Robbie are behind them and Pacifica is with McGucket. Then when Pacifica's hair is on fire, she is next to Robbie.
There was no reason they had to erase Stan's entire mind with the memory gun when Bill got in his head. They could have just set it to erase "Bill Cipher" from his memories and that would have had the desired effect of destroying Bill while he was in Stan's head.
Ford asks if anyone has a pen or pencil to make the Bill Cipher Wheel, but he has a pen in his pocket.