clearly clueless codes customers date discount download expiration hour interests limit link noted options page select validity

Under More Options, I can specify Expiration Date and Time and Download Link Validity. I am clueless about what I should select for these. What works in both my and the customers best interests?

Expiration date is not for the download link, but for the discount codes. That's clearly noted on that page. An hour limit of 0 and a download limit of 5 work really well.