Confirmed. (5.20pre19)
Disabled "Preview notes when inserting or editing" doesn't prevent this here.
FIXED (5.20pre21)
Not sure if I would call it a bug tho. IMO it should record the mouse clicks as notes in all recording modes (with an option to disable it).
I made a Feature Request for this some time ago:
http://forum.cockos.com/showthread.php?t=72027