Hi, I had a look at what you're refering to (I'm on thin ice now)
and I think it's because the ZIPs for disk 1 (ms dos) and 4 (dos+ 1.2 os, boot files, gem paint) do contain a disk image each.
There are further files in the .cfi images; and the content of inside these .cfi image must be written back to a physical floppy disk using that fdcopy program (on DOS).
Or maybe it's possible to extract them using WinImage, not sure.
Or maybe try pc1640 disk set instead? It uses an .cfi floppy image for disk 1 (ms dos) only.
The other disks (gem) are ZIPs with normal files, it seems.
(Disclaimer: To my defense, cp/m and gem have become open source by now.
So dos plus, as a cp/m-86 variant, might be included here.
The supplied dos 3.2 can be seen as more of a start-up disk, maybe, if we're generous.)
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