Jen:
How did you try to open Triplea saved games? As you may have found out just double clicking the file doesn’t work. Using “open with” won’t work either because Java programs never show up in the list of programs.
To use a Triplea saved game file you need to put the file into the savedGames folder in the Triplea directory then open the saved game from within Triplea. That should work.
As for the firewall issue, if you configure your firewall to allow Triplea to use port 3300 you should be good to go. That’s the default port, however you can choose whatever port you like. But if you do decide to use something other than 3300 you need to change the default in Triplea to match it. ~ZP