You do not download updates randomly from the internet, so I don't know what you found. You have to register your game with Stardock. Do that here, then redownload the entire update game, since your installation probably got screwed up with whatever you did. It will then be up to date.
BTW I would get the version of Maelstrom for Diplomacy 1.34, preferably the expanded pack, its a great mod.