In one frame before Steven asks "What are you gonna do with all the money?", his right eyebrow disappears.
When Steven shows his gem, Greg's tan line on his right arm is drawn with outlines making it look like a shirt sleeve.
During the song "Mr. Greg", when Greg, Steven, and Pearl are being held above the employees and moved to the dining table, and again when the elevator door opens, Greg's tan lines on his legs and feet are reversed.
In one scene, when Pearl was singing "It's Over Isn't It", Greg's hair was the same color as his beard.
At the beginning of "Both of You", Greg's beard is colored darker than his hair.