Well, we were thinking at first only we can give a special rate to affiliates from the admin side.
However, later on perhaps we could put a box for the user to choose from a list of options. For now though we are just thinking of making it only so just admin can give a special rate to some special users.
We can change at any time yes.
Also the mod to make it so the user can see which file made him the sale, is this possible or can't be done very easily?
Please tell us how much it will cost for these mods.
Thanks for your help again.