Get Quiz will open a window with a list of the quizzes you have saved, select the quiz you want and close the window. Restart Quiz brings the quiz back to the state it was in when you first loaded it, with all questions in the queue, save any you have deleted.
By far, the button you will be using most is the Next button. To see the next question you will click it, and to see the answer, you will click it again, and so on. The Append button comes in handy once your quiz is down to a small number of questions, or when you want to combine two quizzes. If you have a quiz left on, for example, chapter 1, with only three questions left in it, you may want to click the append button, then select the chapter 2 quiz, and append the chapter 1 quiz to the chapter 2 quiz.
The Add Question and Clear checkbox allows you to choose whether you want to add a question and leave the old question in place so you can modify it to turn it into you next question, or clear both text boxes immediately after you click Add Question.
Questions, followed by the black text box with a green number in it, lists the total amount of questions in the quiz. Remaining, followed by the black text box with a green number in it, lists the questions that you have left in the quiz to complete.
The Shuffle check box will randomize the order of the questions if you click it before you open the quiz, otherwise you will get the questions back in the same ordered way that you put them in.
Generally, you will want to limit your quiz sizes, especially if you are randomizing the question order, to approximately fifty questions, to prevent you computer from bogging down in the process; this is not a rule written in stone, results will vary depending on the processing power of your computer, it is only mentioned so you are aware, and if you notice any slowness, to many questions in one quiz could be the likely cause.