Tonal Centers Parameter in Hookpad

I’m not very clear on how the Tonal Center (Octave) parameter of Hookpad works. Does the software automatically ensure that harmonies work regardless of setting? For instance, if I set the bassline octave to .4, is it transposing everything to be in key or is it just shifting is 40% up? There doesn’t seem to be much documentation on what’s going on behind the scenes.

See this post.