If the Test Report error went away, sounds like you adjusted the correct eddy, but perhaps went too far in the "insensitive" direction. IMHO the easiest way to adjust is to go into Switch Edges, raise the playfield, adjust the pot, test with a ball (while the playfield is still raised), both watching the LED and listening for the "bong!" of Switch Edges. And did I mention that the pot adjustment is REALLY sensitive?
And there are a total of three eddy sensors: one in front of Red's mouth, and TWO in front of Ted's mouth, one on either side of the dozer blade. All three use the same kind of eddy boards with the same adjustment procedure. Might as well tune them all while the playfield is up.
To your other question: when you're in a game and the ball hits Red's mouth, she'll generally shout in surprise and/or yell at you angrily... if the "Big Millions" arrow was lit, the DMD will show an award like "BIG MILLIONS 6,000,000".