Make sure you are selecting the regions and dimensions (like velocity splits) that you want to affect and then make sure you hit the apply button in the mix layer tab or nothing will happen. Also, make sure you are hearing live updates. If the loader light is not green, you will not hear some edits in real time. You may need to reload the sound which will either cause and instand partial save(Yellow light) or in drastic changes, a full save of the whole file. (orange light) If you still have trouble with it, feel free to contact us at NemeSys.
Dave of NemeSys