The follow-up to the No. 1 best-selling train simulation PC game,* “Train Simulator 2” provides the opportunity to command a 200-ton modern diesel locomotive or operate a steam-breathing behemoth from the past. Taking cues from the exacting standards of quality and realism associated with the “Flight Simulator” product family, this latest edition of Microsoft’s “Train Simulator” series charges full steam ahead from where its predecessor left off.