Dont have definitive answer, but you can try. Some changes done to TMO25 may not "kick in" for your old saves; I'm thinking about changes (if any) to upc files: the game takes some of them, or information contained within and stores it in your docs folder (with your saves - 'upc initial" and such); I think the game doesnt update them - doesnt check main game folder for any changes - as far as I know. You may end with TMO25 mixed with TMO2.2 equipment availability dates and so on; or you may end up with your boat with no deck gun or wrong radar position on CT
