If CAPS-Lock is activated, the changes in the volume/pan evolution will apply to all tracks.
That's a direct quote from the Help file
(you should've looked there first!)
If all you want to do is fades:
If you want to perform a fade in/out, you can select the time interval during which the fade should take place by dragging with the mouse on the track and then selecting the Edit/”Volume/Pan drawing”/Fade In/out menu option.
Here's another really cool addition:
Holding down the SHIFT key allows to freely draw the evolution of the volume (i.e. every move of the mouse will create a new node in the piecewise linear waveform).