I am trying to get a Lenovo Thinkpad USB Keyboard, product code 55Y9003. Unfortunately it doesn't come with drivers for Mac (it is a PC keyboard) and the Fn key (and a couple of others don't work out of the box. The Fn 1-12 keys themselves work (as normal function keys, not Consumer Keys) but the Fn key doesn't register at all. Three other keys have no effect - the menu key between right-alt and right-ctrl, and the two web-browsing keys on either side of the up-arrow.
Is there anything I can do or should I just return the keyboard?