It's okay to book in WL in Tatkal (It will show as CKWL xx), and normal chances of getting confirmed. If it is not, the whole fare will be refunded minus a clerkage of Rs 20 I think. As for confirmation, it depends on a variety of factors. But it will be refunded if not confirmed, certainly. A e-ticket or ticket booked with credit/debit card will be reversed automatically within 2-4 days. An i-ticket has to be cancelled across the counter as per the normal procedure.Good wishes and Happy New Year