I would recommend that you use Generations and your family file as a stand alone computer and not as part of a network. Try disconnecting the network, then install Generations from your program CD, then copy your .uds family file to your Sierra/Gen? folder, where the ? represents the version of your Generations such as 5 or 6 or 8.
Also please be aware that your old Sierra version of Generations is not compatible with recent versions of Windows. You really need to upgrade to the latest Generations v8.5a which is XP compatible and works on Vista too.