It looks like a program that runs in the background would be very difficult to set up. There's a lot of security preventing that, so people won't steal passwords and stuff like that. I might have to make a traditional typing test, which would be easier anyway.
Also I collected some data on Master Key for 3 different layouts: QWERTY (which I can do 75 WPM on), my layout (65 WPM), and Colemak (20 WPM). I made a little diagram showing which areas were fastest. Lower numbers are better.
QWERTY:
? 4 1 1 3 2 4 3 6 7
1 4 2 3 6 1 5 5 5 8
6 7 6 2 7 1 3 4 7 ?
My layout:
6 4 2 4 5 ? 6 3 4 5
3 3 2 2 2 4 5 1 3 3
6 5 7 4 7 2 5 6 7 ?
Colemak:
? 6 6 5 6 2 5 1 4 ?
4 4 5 3 5 2 1 1 4 3
7 ? 7 1 7 4 5 3 4 ?
I notice that in general, I'm fastest with the home row on the right side. But more than position, I'm faster with the more common letters. On QWERTY, I'm best with E and R, two common letters that are next to each other in an easy roll.