Abstract: A subsea equipment operations arrangement for an offshore platform or vessel includes a working deck with an opening to allow passage of subsea operation equipment to and from a position below the working deck, a lifting structure positioned above the opening to lift and handle heavy subsea operation equipment through the opening, and a system for transporting the heavy equipment laterally over the working deck to and from the opening. The system includes a rail structure on the working deck that supports and guides a movable carrier configured to carry the heavy equipment. The opening extends in a lateral direction from a lifting position below the lifting structure to a point aside the lifting position. A first deck section is movably arranged in the opening, covers a portion of the opening, and includes rail members.