The MGD2 only accepts certain filenames, and these filenames
must be specified in an index file, "MULTI-GD", otherwise the
MGD2 will not recognize the file.  In the case of multiple games
being stored in a single disk, simply enter its corresponding
MULTI-GD index into the "MULTI-GD" file.

Super Famiciom:

game size       # of files      names           MULTI-GD
================================================================
4M              1               SF4XXX.048      SF4XXX
4M              2               SF4XXXxA.078    SF4XXXxA
                                SF4XXXxB.078    SF4XXXxB
8M              1               SF8XXX.058      SF8XXX
                2               SF8XXXxA.078    SF8XXXxA
                                SF8XXXxB.078    SF8xxxxB
16M             2               SF16XXXA.078    SF16XXXA
                                SF16XXXB.078    SF16XXXB
24M             3               SF24XXXA.078    SF24XXXA
                                SF24XXXB.078    SF24XXXB
                                SF24XXXC.078    SF24XXXC

Mega Drive:

game size       # of files      names           MUTLI-GD
================================================================
1M              1               MD1XXX.000      MD1XXX
2M              1               MD2XXX.000      MD2XXX
4M              1               MD4XXX.000      MD4XXX
8M              1               MD8XXX.008      MD8XXX
16M             2               MD16XXXA.018    MD16XXXA
                                MD16XXXB.018    MD16XXXB
24M             3               MD24XXXA.038    MD24XXXA
                                MD24XXXB.038    MD24XXXB
                                MD24XXXC.038    MD24XXXC
32M             4               MD32XXXA.038    MD32XXXA
                                MD32XXXB.038    MD32XXXB
                                MD32XXXC.038    MD32XXXC
                                MD32XXXD.038    MD32XXXD

PC Engine:
game size       # of files      names           MUTLI-GD
================================================================
1M              1               PC1XXX.040      PC1XXX
2M              1               PC2XXX.040      PC2XXX
4M              1               PC4XXX.048      PC4XXX
8M              1               PC8XXX.058      PC8XXX
