Kristen, what did you not understand, or what did you miss?
George and Susan's parents got together for dinner, and the Costanzas brought a Marble Rye. Susan's parents forgot to put it out, so Mr. Costanza stole the rye out of anger.
George was embarassed by this and decided to sneak a new rye in (a couple of days late even) and put it in the kitchen, hoping that Susan's parents would assume it was there all along.
He had gotten Susan's parent's out of the house by having Kramer take them for a Handsome cab ride, but the horse had gas (per Kramer feeding it Beefarino) and they came back early, before Jerry had a chance to get the Rye to George, so Jerry adn Kramer were trying to through the Rye through the window (which is a couple of floors up) and couldn't through it high enough, so George got a fishing pole and reeled the rye on up, but alas, he was caught.