Complex sentence: The Game is not compatible with Windows XP by default, preferring the operating systems of its time (1997), Windows 95/98, however only small adjustments to the configurations of the game have to be made before it works upon Windows XP.
Split into simpler sentences: The Game is not compatible with Windows XP, preferring the operating systems of its time (1997), Windows 95/98. However, only small adjustments to the configurations of the game have to be made before it works upon Windows XP.