The current manual control is bobo as hell, hopefully the new release coming addresses it. I almost always end up running everyzone on accident.
Plus if your hands are wet it plays hell with the touch interface and I preform unintended manual runs.
An emergency stop can be found in the activity log for the schedule if it is running but the 2 times I have needed it I was in panic and just put the system in standby.
The geyser in my front yard, "old costful", always induces panic for me....