At about 9:05 Courtney Thorne-Smith walks to the left and a studio camera is visible on her right. Only noticeable in the widescreen version.
at 12:51, you can see someone else as "Andy" other than Larry Joe Campbell. It is really quick, but you can see a dark haired man where Larry should be. Guess they had other actors trying out for the role of Andy. It is only visible on the widescreen version.