Yep, and this is where it all gets a bit complicated for my small brain, but I think I'm correct now in that you should be increasing your preload until the correct sag setting is achieved.
Once this has been done, you then should do the front the same way. Once that has been done, you then need to look at the loaded sag (ie with you on it (kit included))...and obtain figures suitable for your purpose, ie road or track.
If you find you cant obtain a suitable loaded sag figure whilst still maintaining the static sag at the correct setting, then this is pointing to incorrect springs for your weight.
As with anything to do with suspension...this is probably all bollox!
Someone please correct me if I'm wrong.