Copying files from a Saturn disc

[TeridaxXD001]

There are certain types of files I simply can't copy from a Saturn game, in this particular case, an .SFD file from NiGHTS Into Dreams... I tried copying from a .BIN/.CUE combo mounted to a virtual drive, as well as from the actual disc itself, but I get the error "Invalid MS-DOS function." I assume this is due to the fact that it's a Mixed Mode CD, meaning it has a couple of data tracks containing the actual game files as well as several actual Redbook/CD Audio tracks containing the majority of the game's background music.

I can copy any other file type, including .PRS, .CPK, .TSK, .TXT and .ADP, as well as "0NIGHTS," which has no extension, but not .SFD. Why not?