In the main Timeline view, temporarily turn the track with the MIDI item into a folder track. Place the track with the snare audio as the first and only track in the folder, just under the MIDI track. Select the MIDI item by single-clicking and activate the in-line MIDI editor for that item. On my system, the keyboard shortcut key is: E.
If you don't see the audio waveform from the underlying snare audio, go to Preferences-Appearance-Peaks/Waveforms and activate "Draw faint waveforms in folder tracks".
You should be able to edit the MIDI notes right on the main timeline.
https://www.dropbox.com/s/1dulwmbxwh...ample.JPG?dl=0