I use USB drives 64, 32 and in deed I use couple 128 Gigs, as long they are USB 3....And Eileen is correct, that message on that keyboard is NOT because of the USB size, is because it has a corrupted file....
I have seen that screen some times, and that is the case, a corrupted file, could be a Multipad, Registration, User Voice, User Style....
My 2 Cents.
Manuel