I use Midihub to add some extra modifiers, controlled by a Beatstep, to my Korg Prologue, but I got frustrated because the LFO is bi-polar.
This pipe uses an LFO as a free running source sending out CC messages, that are all transformed to a fixed value. A second LFO changes that value up and down.
I have mapped both the fixed value and the depth of the second LFO to a MIDI controller knob on the BeatStep. The fixed value is doubled before sending it to the second LFO, making it always identical to the depth setting and resulting in a uni-polar LFO.