I have access to a Mac SE, non-FDHD, a Mac Plus, and a Mac Classic II. I currently have 400k dsk images for System 4.0 on the SE, but Disk Copy 4.2 doesn't recognize them at all, and Disk Copy 6 refuses to write floppies claiming that I need a drive that can write 400k floppies, which the SE should be able to write (I'm able to initialize a single-sided disk). Are the images I'm using not valid for Disk Copy 4.2? If they aren't, where can I get valid images? All the ones I've found seem to be intended to be used with emulators.