HELP with MEHAFLASHROMSCC+SD

Hi folks,

once upon a time I erased the "A" rom drive of the MEGAFLASHROMSCC+SD

Now I'm trying to restore it with

opfxsd romdisk.dsk /id

it say

Too big file...

I downloaded the file from the CARTRIDGE SHOP official page.
What could be the problem?

Another question is:
how to write on a real SD the SD_IMG file that seems useful to restore the MFRSCCSD ?

Regards