For information: - Instead of launching the autorun, run setup.exe directly from the DVD (this avoids having to register JustForGames). - Start the first time the "normal" version (= non Venice) of the game, it should be updated. - Start the extension this time, the game should again be updated. - If you do not have a net connection, patches are recoverable forum UBI. (Search "[Anno 1404] Patch 1.3 and 2.1 available" on a search engine)
After you apply patches, you should not need the CD key.
Edit: Thanks to delete my amazon have yet useful link ...