Coxheath is not mentioned on any list of estates in Jamaica that I have seen. I am indebted to Mr E Mordey of the UK for the suggestion that this area is named after Coxheath in SE England, which was a major encampment for soldiers awaiting transportation overseas during the 18th century.
If this is so, and if there were indeed a detachment of British soldiers camped here who were there long enough to name the place, it would tend to support my hypothesis that the ruins at Windsor are in fact of military origin together with the Troy-Windsor trail. More research is needed!
Ted Mordey's ideas on the origin of the name Coxheath/Cocks Heath are also interesting.

The boundary was marked by two substantial (and expensive!) stones at the Sherwood Content road junction to Windsor; one stone was uprooted during road widening.

Have a drink at Ms Lily's bar in Coxheath.
Ms Lily's brother, Wellesley "Gideon" Bolt, is part-owner of "The Bungalow" or "The Little House" at Windsor.
Incidentally, Gideon's son is "Lightning"!

This area is now owned by Kaiser Bauxite and is possibly threatened by mining operations.