On both mac and pc, you can use the comma and period keys to move up and down through the Basic Development menu, then when you get to the desired function, like Exposure, the plus and minus buttons move the exposure .1 at a time in either direction.
On the mac, but not w7-64, holding down the option key while tapping the plus or minus move the exposure in increments of .02.
I never would have discovered the Option key function if I hadn't tried it because of this thread.
just another $.02