I have the SR-1, which I'm thinking is the acrylic version of your call.
Did yours come with a DVD? The DVD that came with mine was pretty helpful.
You'll get the buzz eventually. The reason they talk about getting the buzz is that once you get the buzz right, you have your air right.
Work on your air control, hand placement. For a deep goose, you should be calling into a cupped hand, with the fingers around the bell somewhat closed.
You should be blowing air like you would fog up a pair of glasses, then transfer over that breath into a slight cough.