When Max, 99, and Zelinka are shown from the back and above walking towards the place where Prof. Dante was kidnapped, 99's hair is down and out of her cap. In the next shot and throughout most of the episode it is tucked up inside her chauffeur's cap until she removes her cap and Max discovers she's a girl.
Two KAOS agents stand by a door which shows several bullet-holes. Cut to Max firing a machine-gun. Cut back to the KAOS agents, and the bullet-holes are gone.
The gun in a KAOS agent's hand morphs from a revolver to an automatic to a revolver again.
When Max is locked inside the closet at the concert hall, the door is hinged on the right, with the handle on the left side. He pulls his gun to shoot the lock off, and in the closeup of the handle being shot, it's suddenly on the right side of the door. Cut back to the wide shot, and it's back on the left side.
When Mr. Big presses the button on the Inthermo Weapon, Max, Agent 99, The Scientist, and Fang are in a dinghy some distance away from the fake garbage scow. The dinghy is clearly tied up to another boat at a dock and not in the middle of the Hudson River.
As Max and Agent 99 drive from Long Island to NYC, palm trees are clearly seen in the background.
The top two feet or so of the boom mic is visible in sun glare on drivers side windshield of the 1965 Lincoln limo during dialog. When Max moves away, the boom can be seen going over the roof of the car to follow him.