The image I converted was a bit weird tho, and I get no music (and I think you need the digital board to get SFX because it just says SFX N/A in the menu)
It's a CD-i Ready disc; without SFX is plays music from the CDDA audio tracks. To get SFX you need 1 MB of extra memory, nothing else.
The DV cartridge is one way of getting that, using a CD-i 605 another (it has more memory). JD, could you just add 1MB of RAM somewhere high (E80000 comes to mind)?