Kandi,
I'd thoroughly recommend the Gen Nav refresher weekend at BGS - my laptop almost went out the window a handful of times when trying to learn Gen Nav, and the weekend really sorted me out. Well worth the travel and cheap hotel!
Having said that, my Gen Nav exam had only 1 question on any sort of stereographic, I don't recall any grid nav, and I had 3 or 4 flight plan questions which were an easy win!
FR