This expansion pack expanded the PC CD-Rom version of the game only.
From the manual:
WELCOME TO WORMS REINFORCEMENTS
The "MUST HAVE" game expansion pack for WORMS, the best selling arcade strategy game form Team17 and Ocean!
This pack will grant you even more fun, action and options to the game than you ever though feasible! The ability to add custom drawn backgrounds, custom sound sample sets and play over Network (Local IPX network) will take you to new heights of the Worms experience!