In case you want to keep the same settings and scripts, you could do this:
- back up the CHDK folder on your current card
- format the other card (filesystem should be FAT16)
- copy the CHDK folder to the other card
- install CHDK via STICK on the other card (this step will also update the necessary CHDK files in the CHDK folder)
The above should work for cards not bigger than 4GB. Note that 4GB cards are formatted to FAT32 by default (in camera and on the PC), so this step needs to be done on the PC, choosing FAT16 as filesystem.