I think in fact all grey contacts mod, is insted you've got diferent contact colours for diferent ship tipes in your nav. map ,with this mod they all are grey however tipe of ship apears in your nav. map....
Before you had green for neutral ships, red for anemy ships blue for friendly ships, not now, now you've got to pay more atention to what your eyes say to you and radio contacts as whell the sonar man...