Continuity mistake: When Peridot is looking for parts for the machine, she pulls the microwave from its mounting below the kitchen cabinet and drops it on the counter. After Steven stops her from wrecking the house by telling her he has a better idea, the next shot of the Crystal Gems shows the microwave behind them in its original position.
Suggested correction: This is a time jump, that they didn't want to show her putting the microwave back in.