1: 46mm wheel nut side/ 41 mm sprocket side/ 28mm front wheel
2: The tool for the hub should be in the tool kit...looks lke a large C spanner with a box section piece for the handle.
3: Torx 7 I think?
4: No problem with connecting up a charger to the battery...have optimate terminals on mine.
5: Tyre pressures are a personal thing...but 36 psi front and rear will put you close. Theres a great post by shazzam somewhere on here about tyre pressures and working them out to suit your riding style. Try a search on it.
HtH
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