there isnt a site to download a legal free full version, if you want a legal full version of it just buy the full version. however most people when running 3dmark just use the stock settings (the ones from the free trial version) and the adjustments are mainly used by hardware reviewers to give additional info in reviews.

in the end like i said just use the trial version or if for some reason you have extra money kicking around buy a full version though you wont really need it.