1) I would use a little of your chosen tyre additive to clean the tyres, then apply a bit more for the traction element. When you start picking up speed you'll learn the little bits to make you quicker.
But that should be a good start
2) I would charge at 5amps. 1C is the BRCA (UK guidelines, as is ROAR to thr USA) so 4.6amps for a 4600mah set of cells is considered safe practice.