I just purchased the Softstep 2 along with the MIDI expander. I am using it to control a G Major Guitar Processor. Previously I used an ART X15 and it worked great. I am not looking to overthrow the world here. I am just sending PC messages to switch guitar presets (that works just fine) and CC messages from an expression pedal on CC#7 to control volume. To control the volume I am using a Moog EP-3.
I use the advanced editor . The pedal calibrates just fine. the resulting graph is a nice, mostly linear 1:1 slope. The pedal outputs MIDI CC signals and does control the volume, however, for about 85% of the pedal travel there is no level change and then in the last 1/4" of the travel it blasts to full volume.
I changed the display on the pedal so I could watch the MIDI signal that was being put out as I operated the pedal. Clearly the output was not linear. at 85% pedal travel the number was about 20-25 and then all at once it it piles on. I would say that it looks exponential or logarithmic in nature, but when I tried those they were slightly worse than the linear setting. Based on this it seems that there might be something wrong with the program that determines just what exactly linear response is.
I have been in contact with the fine folks at KMI and they have tried very hard to help. I have reset sensitivity and calibration for hours trying different set combinations but to no avail. I have replaced the adapter and that didn't help either.
So I am at wits end and hoping that a user might have something that could help. I use this for live performance and it really needs to be bullet proof. And it is pretty cool, but if I can get it to work soon i'll have to return it.