Huma posted about a VMU Rip Transfer Utility at http://www.consolevision.com :

While browsing some Japanese DC sites, I came across a seemingly old VMU utility for dumping it through the BBA or coder cable.

This is the program for getting files from first VMU.
It’s saved as DCI Nexus format. thanks idea, for Chiha.

vmurip.bin: For dcload-ip (This binary use dcload-ip’s API)
vmurip.srec: For serial-slave (It download using YMODEM-Batch)

Those interested should head on over to the site linked above for the download.