From my submission of Riven (5-CD), the middle 3 CDs below don't have another (USA)-only version, so I'm proposing the following renames:

http://redump.org/disc/43319/ -> Riven - The Sequel to Myst (USA) (Disc 2)
http://redump.org/disc/43318/ -> Riven - The Sequel to Myst (USA) (Disc 3)
http://redump.org/disc/43317/ -> Riven - The Sequel to Myst (USA) (Disc 4)

There is a logic behind the naming tongue (USA, Europe) dump is the "parent", so that's why your USA one has (Alt)