How to use the Yamaha C Display electric bike system 

Yes you can in the settings menu

A few older machines may not have this functionality. If your ebike does have it you will press and hold the up button for a few seconds to activate/deactivate the automatic mode. Then A-Mode or A appears on your screen to show it is activated. I hope this helps you. :)

Yes and it is fitted under the unit. You have to remove the screen from the handlebar mount to fit it (a twist cap you can open then using a coin)

Yes you can in the settings section. It gives you options to reset specific data sets like trip distance and a few others.