Sorry to take so long to reply MrFitz , I don't look in here that often.
Go here:
http://www.vguitarforums.com/smf/index.php?topic=6895.0 It's the 5th post down
and apply the same principles except with the vs100. you can either work it out or let me know and I will post the actual inf as I changed it. I put this link because he explains well how to bypass the driver signing issue.
Basically in the [Roland.NTx86.6.2] section, delete what's there and put
;; Windows8
%RDID0099DeviceDesc%=RDID0099Install, USB\VID_0582&PID_00EB ; VS-100
and in the
[Version] section delete the line beginning with CatalogFile=