Hi Puma,
I am not an expert at this, but this is how I beleive it works;
Many affiliate programs will store a cookie within the users browser with a 'tracking ID' identifying you as the source of the visit. Wether they sign up with the download link or browse first, this cookie should still be detected later on when they do decide to download and register.
Cookies have varying lengths of expiration (I think 90 days is the maximum) so even if a user bookmarks the website and returns within this period you should still be credited with that player (although cookies can also be overwritten when referred by somebody else later on) These parameters will vary greatly between affiliate programs.
I managed to increase my download to registration ratio by adding 'nofollow' tags to all of my links, as most of what i thought were my visitors were actually search engines doing there regular crawls - these all get reflected in the stats.
MrKay
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