SoundDiver's Microtonal Tuning Editor

Have any of you used SoundDiver's microtonal tuning editor?

It seems pretty straight-forward except for the fact that there seems to be
no way to set pitches at even remotely resembling high precision. If you
move the mouse even a single pixel, the pitch jumps 40 cents or so, whereas
I want to be able to adjust down to the single cent.

Anybody have any thoughts on that?

Thanks, folks!