You will get the participation fees and not the processing fees as the processing fees is non refundable. Though the official website hasn't mentioned any timelines for refund of the fees, you can expect the refund atleast by 10-15 business days. Sometimes it takes longer and sometimes it is refunded even quicker. And there is no separate process that you need to follow for the refund. If you havent been allotted any seat, the amount will be refunded.