I've discovered a workaround for the V-Studio 20 Windows 8.0 driver for use on Windows 8.1.
After downloading a fresh copy of the 8.0 driver 1.0.0 vs20_win8d_v100.zip from Roland, extract it;
After extracting vs20_win8d_v100.zip go to the subdirectory E:\Users\Your Name Here\Downloads\vs20_win8d_v100\vs20_win8d_v100\Files\64bit\Files ;
Edit the file RDIF1106.INF using Notepad;
Locate the section which looks like the following:
;---------------------------------------------------------------;
[Manufacturer]
%MfgName%=Roland,NTamd64.6.2,NTamd64.6.3
;[ControlFlags]
;ExcludeFromSelect=*
[Roland]
;; Windows7 - Windows XP 64
;; not supported
[Roland.NTamd64.6.2]
;; Windows8
%RDID0106DeviceDesc%=RDID0106Install, USB\VID_0582&PID_0117 ; VS-20
[Roland.NTamd64.6.3]
;; not supported
;===============================================================;
Copy the line %RDID0106DeviceDesc%=RDID0106Install, USB\VID_0582&PID_0117 ; VS-20 from [Roland.NTamd64.6.2] to [Roland.NTamd64.6.3] as follows;
[Roland.NTamd64.6.2]
;; Windows8
%RDID0106DeviceDesc%=RDID0106Install, USB\VID_0582&PID_0117 ; VS-20
[Roland.NTamd64.6.3]
;; not supported
%RDID0106DeviceDesc%=RDID0106Install, USB\VID_0582&PID_0117 ; VS-20
Save the file
Hover over the bottom right corner of the screen to retrieve the charms menu;
Click or tap the Settings Charm;
Click or tap the Change PC Settings link on the Settings Charm;
In the PC Settings Menu, select Update and Recovery;
In the Update and Recovery Menu, select Recovery;
In the Advanced Startup section, select Restart;
After the restart, choose Troubleshoot;
then choose Advanced Options;
then choose Startup Settings;
then choose Restart;
After restart you will see a list of startup options, choose 7;
When the restart is complete goto the directory E:\Users\Your Name Here\Downloads\vs20_win8d_v100\vs20_win8d_v100\Files\64bit and click install.
You will get a warning message during install saying Windows cannot verify the manufacturer of this driver, choose install anyway.
Bob is then Your Uncle!!
I apologize for lots of detail but I cannot assume any user is familiar with any step.
Glenn Corcoran.