Good tips, thank you.
Yes, old Workbench works on my Windows 10 machine after some fiddling around (Java had to be installed manually).
I picked up a Variax Standard and have briefly checked out the "virtual capo" feature (press and hold the Model knob 2.5 seconds, select the Alt Tuning knob position, play strings one at a time relative to fret 12=standard, press and hold Model knob to store).
I'm not sure I've done the right thing as _some_ alt tunings sound rather artificial with a strange pulse noticeable on the lower strings that reminds me of some other pedal I've used, a hold or harmoniser or something. I've reloaded the firmware and loaded the standard bundle but it makes no difference.