Just FYI,
I have an older ASUS MB (P7P55 D Evo) and I can get into bios with K90 firmware 1.18 BUT I have to use a specific DEL-key of the numeric keypad, the other under the Insert-key is not working.
What else - the numeric-keys above QWERTY-keys are not working in Bios, only keys in numeric keypad are working. This is independent of the state of Numlock -key.
Otherwise K90 is working during POST and in Bios.