The way you will want to set this up is as follows: In the setup pages in your account under "DEFINE YOUR CAMPAIGN RULES," change it to say, "I would like to reward campaign participants EACH TIME when TEN of their friends CONVERT ON my website. I want to reward them WITH COUPON CODES from this single-column XLS file *.xls." The way it would work is this: The participant in your referral campaign would receive a coupon code each time they referred 10 people who purchased on your website. You would need to set up your payment processor to accept this list of coupons and also to allow multiple coupons on one purchase, for example, when one participant has referred 20 people, and they have two coupons they want to use at the same time.
This is the easiest way to set this up to work automatically. The participant will receive a congratulatory email set up by you, with their coupon code, when they have successfully referred 10 people who have converted or purchased from you.
You can also give the person they are referring a coupon code if you would like. Just don't forget to set up the code in your payment processor so it will be automatically accepted.