> 3. The download is aborted before completion. If restarted (Z-modem),
> the download completes.
I have not had good luck with restarted downloads - therefore,
I myself would suspect that the "composite" zip file (made up
of two separately downloaded pieces "stiched" together) DOES
have something wrong with it.
> 4. The down.zip file cannot be unpacked by IMPORT.EXE or by
> UNZIP or PKUNZIP.
Try unzip of the file you started with on the unix system.
If the original file can be unzipped, but the downloaded
copy can't, chances are it was the download that corrupted.