Need help with some stuff with Ritual/Path magic.

[Humabout]

Idhmbwm, but

You use the effective skill used to cast the spell to overcome resistances.

You cannot buy up Path skills above your cap (to my understanding, although it makes little sense to even attempt to anyway).

You use the lowest effective Path skill required by the ritual, at -1 per additional Path skill past the second to determine the casting roll. That's the effective skill for the spell.