Just started to try the demo. And within minutes stopped because it was impossible for me to correctly set it up.
The program chose the Dutch screen/manual (OK, I do have the Dutch version of Mac OS X 10.6.3). So far so good. Then, however, I had to pick the correct keyboard. A choice of two Dutch keyboards: the one with Dutch QWERTY or with Dutch (Flemish) AZERTY layout.
It became clear that the program is not up-to-date, since the keyboard layout differed too much (e.g. the Return key) from the current Apple keyboards (mine is from last year, a Dutch chicklet-style keyboard with numerical block.
To make trying out this program comfortable enough, users should be able to pick the correct keyboard layout. Hopefully the developer will have a closer look at current layouts and add these to the preferences.
What I do like about this program is the help with correct finger position. A program like aTypeTrainer4Mac still doesn't have this possibility, as far as I know.