Note: If you use the Send Notification option,  The URL Generated by DNN contains the VendorID  not the AffiliateID as the Affiliate ID parameter.
E.g:
•Vendor ID=5
•AffiliateID=1
•URL Link = http://site.com/Default.aspx?AffiliateID=5

As this value is then used by Storefront to record the referring affiliate in the SalesOrder it will cause the orders to be wrongly allocated.

I would recommend creating your own notification email for the Vendor / Affiliate, ensuring that the URL contains the correct value.
e.g
URL Link = http://site.com/Default.aspx?AffiliateID=1

(Both the Vendor and Affiliate ID are system generated primary keys, so cannot be changed - and may initially be in synch)