The crossfader can be steered by playing back the transition and using the mouse on the horizontal pad. Any movement you make will be recorded and replayed later

The flat envelope button clears the envelope. It is set to the utmost left position. Useful to start recording your own envelopes

Clears the envelope and replaces it with a linear crossfade.

Cross correlation envelope. Steers the envelope by choosing the loudest of the two songs.

If a manual envelope is drawn, then all positions are relative towards the start of the transition. Lengthening the transition will not stretch the envelope. Moving the transition left/right will move the envelope along. That means that from a practical perspective, it is best to first align the songs, and then edit the envelope.

The crossfade envelope is orthogonal to the crossfader type. It is for instance possible to use the cross correlation envelope together with a isomorphic crossfader.