I took the opportunity with this new keyboard and worked a bit on my uKeeb CircuitPython library. With the custom HID descriptors we can have an NKRO keyboard, but there is a small problem: the bitmap device that this uses won't work in BIOS or with legacy KVM devices, as those expect a BOOT device. Fortunately there is a way around that: when the host expects a BOOT device, it must send you a special message telling you that, so we can switch to that protocol when needed.

The support for receiving that message was recently added to CircuitPython in version 7.1.0, so we can now add the NKRO code to the library by default.

If you are interested in the details, feel free to check the library code at https://github.com/deshipu/ukeeb