GRAND THEFT AUTO & LONDON ADD-ON

[bees]

BACKED UP GTA WITH CLONECD WORKS FINE.
BACKED UP GTA LONDON,LOADS,WHEN IT ASKS YOU TO LOAD GTA AGAIN ,I SWAP DISKS & IT DOESN`T LOAD. IT ASKS FOR ORIGINAL GTA.WHAT DO I NEED TO DO?
I HAVE AN INTERNAL MOD CHIP.
I HAVE TRIED USING A SPRING UNDER THE LID (AS EXTERNAL MODCHIP)