Hi.

The problem is that the empeg/riocar does not use a FAT filesystem like most digital cameras (and other USB removable media) are using. So we would have to add a FAT<->ext2 translation module as well, because Windows accesses USB storage as raw discs (and I think Linux does so, too). The filesystem on the empeg would not be readable by Windows or MacOS without such a translation layer.
One thing might still work: Use a file on the empeg as a taxi storage, mapping raw disc access (via USB) to raw file access (on the empeg's disc). But that won't be just as nice, because you could not access your MP3s that way.
Possible workaround: Wipe your empeg music partition clean, compile a kernel with (V)FAT support, and format the music partition as (V)FAT. The empeg-side USB implementation would still need to unmount the music partition before writing to it, I guess.

cu,
sven