First of all, I absolutely love the program. The one tiny change I would make would be to change the default font in the dictation window from a sans-serif to a serif one because the current one can cause a few 'unforced errors'. An example is in lesson 6, which deals with capitalization, where it is impossible to tell whether it reads 'Al' (as in a diminutive from Albert) or 'AI' (as in Artificial Intelligence).

I know the problem can be easily solved via the preferences window, but it may still be worth correcting.

Thanks again for a great tool!

Thank you for your post! You are right, the font can confuse in some cases. In the character list of the results we already saw this problem and changed the font, but until now I didn't noticed we have the same problem in the ticker of the training window of course.
At the moment we completely renew the software caused by our new online version (which is in beta status now), because we want improve a lot of things and also both versions (software and online) should have the same features, databases, manual and so on. So I will think about changing the font in the new versions. The only thing which bothers me is that changing the font will not look very nice... but that's not really a reason to discard your proposal :)