When Mel Funn walks into Big Picture Studios to sell his idea of a silent movie to the CEO, his fingers are supposed to be stuck crossed together. For a few seconds after entering the office his fingers return to normal before shaking the CEO's hand.
As the car carrying Funn, Eggs and Bell approaches the gatehouse at Big Picture Studios, the windscreen of their car is flat on the hood of the car. But in the following shot from the rear of the car, the windscreen is obviously up when they crash into the lowered barrier, and the windscreen is again down as the car rolls under the barrier.
When Mel's car is lowered when the pregnant lady steps off, a small set of wheels can be seen below the car. These small wheels raise and low the front wheels of the car.
In the commissary scene, a wooden brace can be seen supporting Liza Minnelli's table so it wouldn't collapse under the weight of the suits of armor. Later, the wooden brace can be seen on the floor under the table.