When you guys with driver problems initially plug the cart in, does windows install a generic driver for it? If not, you may have a bad cart.

When you use the app to sign the drivers, did you guys sign all four of the files in the .zip? You have to also reboot in to "test mode." Not doing so results in incompatibilities.

Specifically to the Raspberry Pi, you'll need to be very judicious with your power consumption to get the cart to even power on. When its plugged in to a rev.B Pi directly, the cart works. However it is janky when I plug it in to a powered USB hub, oftentimes I can't initialize anything. My Pi seems to have a number of USB related issues though, I had to switch out two or three very generic USB keyboards to find one that would work.