Couple of things to bear in mind as you dive in to suspension settings on the Skyhook bikes:
Unless the bike is powered on, you cannot set sag correctly. Just a function of how the system works. Without power, the valves in the fork and shock close more or less completely after a couple compressions, from that point the suspension is basically immobile.
I don't think anyone has conclusively proven that the front preload on these bikes does anything. Feel free to test it yourself; I did, and while I don't have access to a spring dynamometer, my manual testing showed zero increase in effective total travel (measured w/ zip-tie), sag, or perceived stiffness regardless of preload setting. Hard to know what that means, the suspension on these bikes uses progressive rate springs, so drawing any useful conclusions about performance without expensive testing equipment is difficult at best. Looking at the preload mechanism itself, I'm not even convinced it's physically doing anything other than turning in place; it doesn't appear to displace along the vertical axis of the fork. How, then, does it work? Magnets, I guess.