I have three tztouch2 units. I fish out of New jersey ports, Manasquan specifically. All the way from inshore to the canyons. I am trying to find the charts for my units that have the greatest and up to date bottom contour details. I called support and they said all charts are preloaded and free. However, I go into into my chart selection and see many are locked and need a code to unlock. So I am not certain that direction is accuragte. Can you please point me into the direction of which charts have the the greatest details on bottom contours?