I took off the glass tonight, and shot a bunch of balls up the left ramp, and watched closely as it made its way down to the wireform just to bounce off at the end and often land right in the drain. What appears to be happening is that the ball is hitting the the end of the rail on the left side, and because it is a bit low, it just rockets right off the edge, or deflects onto the other side. So as you'll see in the image, if you raise left top rail, you will create a barrier that it can't hop, and it will give your ball only the option of dropping into the hole as it should.
Be careful. I did mine with a little frustration in me, and ended up peeling off some of the plating with my pliers. I am expecting a replacement from JJP, so hopefully they can take my notes and make the adjustments for me.
This should be a permanent fix, so please get back to me if you try it, and let me know how it works out.