By some very lucky accident, our friend Oliveira, managed to revive a dead SF3-3 Cartridge and convert it to SF3-2.
We are now trying several roms reencypted to see which conclusions we can draw from it. The only fact till now is that only one kind of cartridge (out of 4) can be revived.
Apparently after re-encryption, the cartridge can work with any game's BIOS, so we could re-encrypt all this cartridges with the SF3-3 BIOS that allows using only 1 single CD for update.
This will also mean that one can have a collection of 6 CDS that will work with that BIOS....