Here are the balls you can play:
1. Two balls behind the head ball -
The ball that's "supposed" to go [just from observing videos of shane and others] is the 2nd ball on the same side as the breaker. It goes into the side pocket near the breaker. The other comes close. When I got the magic ball rack recently, I played with the 10 ball break and was able to play this ball with a little consistency. The sweet spot for me was to put the CB about 1 ball width in from the edge of the box. This sent both balls very near the side... the one on my side went in and the one on the opposite side hit a little low.
If you struggle with the balls coming in too low, you can bring them up a bit by hitting with draw on the cue ball. Maybe not good advice but something to try if you're desperate.
2. Head ball -
This can be played in the side or in the corner opposite the breaker. Shane seems to make it or leave it very near the corner by breaking from the spot I mention above, or maybe a bit closer to center. To play in the side you break from the corner, but then you don't transfer much power to the rest of the rack and your spread sucks.
3. Corner balls -
The two corner balls are wired to go 4 rails around the table and into the corners nearest them. But it depends a lot on speed. More speed tightens them up and makes them hit the side rail instead of the pocket. Usually the corner ball opposite the breaker is moving faster and has more chance to go in. Playing these will depend on the rails a lot, and needs a little luck too (as they must go twice the length of the table without getting kissed out).