I don’t have my Play near me atm, but as I remember things:
While you are dialing in randomization options, it’s only a preview. If you navigate away from the selected steps, things are reverted. Which is a good thing. Otherwise there would be no way back from your randomization experiments as soon as you start turning the knobs. In order for the randomization to be persisted, you need to press Save (or something like that.) The randomization options will then revert to 0 and you can experiment with another randomization on top of the one you just saved (e.g. on another parameter).