As an alternative you can try the XM6 (x68k emulator). This emulator has a option to create a new disk with or without logical formatting. If the new disk is formatted then you can use the DiskExplorer to edit the disk (content). http://hp.vector.co.jp/authors/VA013937/editdisk/index_e.html
PS: If I have time, I will check the MESS driver in detail.