6Effect of first registration with possessory title.
Where the registered land is a freehold estate, the registration of any person as first proprietor thereof with a possessory title only shall not affect or prejudice the enforcement of any estate, right or interest adverse to or in derogation of the title of the first proprietor, and subsisting or capable of arising at the time of registration of that proprietor; but save as aforesaid, shall have the same effect as registration of a person with an absolute title.