With nkululeko since version 0.77.8 you have the possibility to convert all feature values into the discreet classes low, mid and high
Simply state
[FEATS]
type = ['praat']
scale = bins
store_format = csv
in your config to use Praat features.
With the store format stated as csv you will be able to look at the train and test features in the store folder.
The binning will be done based on the 33 and 66 percent of the training feature values.