The front suspension is quite coarse and overdamped, so personally I'd go with very little preload and damping on the front, which isn't going to be affected by your weight and provides a more compliant ride.
The rear is a different matter, so I'd probably start with about 15 clicks of preload and increase if required and 1 turn out on the damping screw.
Overall the CT handles weight very well so you should find a setting that suits you.
