In the main PlayIt Live window, you can right-click on a track in the Track pane and be offered the option of either PFLing it or editing it. It requires three clicks to audition a track. "Instant Preview" (alternative name: "Instant PFL") would add a button of the same name under the Track pane and above the clock. When clicked it would "illuminate" (until you clicked it again to turn the feature off) While "Instant PFL" was lit, you would simply (left-) click on a track in the Track pane and it would immediately begin to play out of the Track Editor Audio Device (ie the same as right-clicking on the track and choosing "Pre-Fade Listen"). If you like, you could bring up the PFL waveform window during playback, in which case the feature would be nothing more than a very quick way to PFL. Click another track in the list and it would immediately start Previewing that instead. Click the Instant Preview button to stop tracks playing. Or the Stop button in the waveform window if implemented.