The old MFR SCC+ could load up to 4 ROMs in each subslot.
The new MFR SCC+ SD can use GM2-PACK (Game Master 2 patched by OKEI) to load Game Master 2 plus up to 3 Konami ROMs (using /Bx option)
So you can make "real" cartridge combinations, like Salamander + Nemesis 2. Even you can load Game Master 2 + Nemesis 2 + Penguin Adventure (or similar combinations)
I've tried what you told.
The patched gm2pack will make the disk offline.
This does not allow to use gm2's disk save features.
Is there any solutions?
This could be a nice feature for the C2, should be possible with correct RCP (or through C2MAN) to configure a combination of ROMs in C2's subslots (as an entry in the bootblock)...
This feature is implemented in the upcoming firmware. You can configure dual-slot in the boot menu. You can have 2 ROMs at the same time. Also FMPAC mono/stereo switch has been added. I don't remember who requested it.
I am working on SCC+ and game combo setup that will allow to use SCC+ and the games that want it at the same time. Then you won't need a separate cartridge.
so I am extra happy! 