Hmm interesting, yeah it's not being seen as a flash cart by windows or the GB USB Smart Card software (Any version) and shows up as an unknown device. The drivers are also not installable even with driver signing enforcement overrider and all of that stuff (Either restarting where it requests or not).

At least it shows up as an unknown device. Now that you've told me its an LED I can look for other problems at least, I'll poke around a bit, thanks.

Edit: Ended up having to restart into startup settings and disable driver signature enforcement, none of the other methods of disabling it were working (dseo13b.exe, CMD Prompt, both with admin privileges).

It's working now though, thanks!

Thanks for replying, and for moving the post.

It looks to be revision 5 (GBU64USB-5), so a bit on the early side. It's definitely resolderable
..

Sorry to invade your nice community here everyone, but any chance somebody can measure a resistor on their GBUSB64 cart? Specifically R6?

Years ago I tried to put it into a standard GB case, and ultimately knocked the resistor off in the process.  I would be eternally thankful to know what it is, now that the price is higher and they're soon to be finished producing them.

Edit: Crap, wrong forum. Sorry guys.