Preview Mode was designed to be a mode of learning that would present the information in the card stack in a continuous flow. If the card stack has the Speak setting enabled for the cards, MemWell will use synthesized speech to help reinforce the material being learned. This mode allows the user to read the card, and view the material, and at the same time hear the question and answer for each card.
The timing delay setting in Preview Mode gives control over how long MemWell will wait between card flips. Because some questions and answers are longer than others MemWell calculates how long the speech synthesis will take and adds that automatically to the delay between cards. This leaves the user free to worry about learning, and not getting the timing correctly. The repeat option will cause MemWell to loop through the quiz material without stopping. This should enable a good uninterrupted learning session. Repetition will help learn and retain the material.