I seem to have lost the ability to select and edit several MIDI tracks simultaneously in the Piano Roll window.
Previously, the Track select section in the Piano Roll display had icons with two eight notes which, when selected,
displayed all data for the selected tracks available for editing in the Piano Roll window. This is no longer available.
It used to be, and is described in the Sonar manual. Was this possibly removed by one of the updates?

The PRV was been updated 4 months ago.

If you want to show events from multiple tracks simultaneously, you must select the desired tracks in the Track pane.
Selecting tracks in the Track pane is similar to selecting tracks in the Track view:
To select a range of adjacent tracks. Do one of the following:

- Click the first track you want to select, then hold down the SHIFT key and click the last track you want to select.
- Click the first track you want to select, then drag down to the last track you want to select.


 

I  should have mentioned that I do select several MIDI tracks from the Track view before going to the PRV.
The issue is that after I do this, I cannot set the focus to more than one MIDI track at a time in the PRV. There is no longer the "eighth note" icon next to each track listed in the right window (track list pane) of the PRV. It used to be there, is referred to on page 1070 "Show/Hide Track button" in the Sonar Reference Guide pdf.
I used to be able to select several MIDI instruments and drag their combined noted in order to align a group of instruments.

And you clicked on the pencil for all the tracks you want see ?

I reviewed the details for Sonar updates and discovered that this "problem" is really a program mod that was released with the 2017.2 update. Previously, if several instrument tracks were selected in the PRV, all the selected tracks were available for changing or dragging individual notes. This has been replaced with the "pencil" icon that allows only some of the control available before 2017.2. I can get around this, however, it requires more clicking to focus on each part of the counterpoint.

Personally I'm not doing more clicks than I was previous to the PRV enhancements. Use the auto lock