I did a little searching about the spectral characteristics of Parkinson's tremors. Most sources say that the tremors are confined to a frequency band of around 4 to 6 Hz, with many of the graphs having a sharp peak and all significant power concentrated into about 1 Hz [1].
Someone needs to email this guy for this little thing, if only to get a good base implementation that was presumably tested in the scenarios this program purports to assist with.
The following BROKEN link shows the directory listing
[1] https://marlin-prod.literatumonline.com/cms/attachment/20616...