[mcgregni]

Glad to have helped! There's some supposition involved regarding the flash metering sophistications, as there is almost no technical data available to us, but other forum members might have further knowledge ......

[kaseki]

...
W.r..t. subject (b), attempts to install the Cactus firmware tool into a Crossover Linux Win 7 bottle have not been successful. .NET 4 is needed, and the installer hangs trying to download it.

Later....
.NET 4 requires a Linux package that the Cactus installer wouldn't know about. So it was necessary to install .NET 4 individually. I can get the Cactus installer to start, but it doesn't see a device to load the firmware to (because I don't have one, at a minimum) so it is waiting for the next step.

In other words, it is possible that the V6/V6II/RF60/etc. can be supported by at least one Linux flavor, in my case Mint 64-bit MATE (and probably any Linux that Crossover supports).

...
To the best of my knowledge the V6II does not emulate a mass storage device.

I hope you can get your Linux solution to work.

Having obtained a V6II and RF60X, I have delved a bit further into Linux compatibility.

• First, the Cactus Firmware Updater V3.07 can be installed into older and newer builds of Crossover Linux running on Linux Mint using any of Win XP, 7, and 10 "bottles."
• Second, Linux Mint itself can communicate with the V6II when it is in its firmware update mode. The V6II uses the Human Interface Device 1.11 spec USB compatibility mode. Linux can interrogate this device using such commands as "lsusb -v" and "udevadm (...)" for more V6II details than one might want.
• Third, the Firmware Updater running under Crossover cannot (so far) see the interface with the USB device. This is likely due to the just-discovered-by-me position of Crossover to not support serial devices. To date their site suggestions for getting a connection haven't been successful. (Essentially, the V6II designated "/dev/hidraw3" by Linux Mint needs to be linked to "/dosdevices" in the Crossover windows part, but variously named links haven't been detected. I have asked Cactus by email what device name they are expecting to see.

Frankly, given the close parallelism between modern Mac OSes and Linux OSes, as well as the heavy Linux usage in China, I am surprised that a Linux based Cactus Firmware Updater is not available.