HVAC system electric diagram help
Some things are shared between models

The N1 neutral terminal and pins 1 and 2 on J1 are probably used on a different model unit that shares that control board, but not used on this particular model.  This allows the manufacturer to save on costs by making one control board instead of two almost-identical ones.

As to that wacky part...

Since the manufacturer was unhelpful and failed to label the part you circled in blue, I can only guess at its nature -- it's most likely simply a connector between two motor wires.