I’m glad you ave found a solution to your problem.
Unless someone has already mentioned it the stop start won’t work with the heater either on hottest or coldest (ac) position. I rang the Honda dealer when my wife’s Jazz wouldn’t s/s, he told me this, and he was right, for my her at least.
Just a note on connecting the -ive charger lead to the bodywork, I would be interested (I’m that dull) in what difference that makes. Since the -ive on the battery is attached to the body anyway.
Your Ctek charger is fine, it just puts current and over voltage across your battery, the same as an alternator. Just make sure it’s in the right mode, ie agm (gel battery) and maintenance mode.
Cheers
Cheers