ugh... how do I hide the velocity lines in the PRV? *SOLVED*

Well, I think I just found a bug that will turn them off. In the controller pane at the bottom left of PRV, click the down arrow of the controller selection drop-down menu. Choose "New Value Type..." then click Cancel in the box that comes up. Velocity lines gone. Obviously you can also just choose a different controller like Modulation that doesn't exist in your midi track and that will get rid of the lines too. Or you can drag the divider between the notes pane and the controller pane to the bottom until the pane isn't showing anymore (Sonar doesn't remember this setting, though, ao if you close PRV and reopen, the controller pane will return).