OK, thanks again Beaky and to all who offered suggestions along the way - Switches are now working!  

Turns out it was a bad connection on IJ4.

Only problem is, how do I get the little red and black button-tops off the old switches to put them on the new set of switches I installed on the coin door? They really seem to be stuck on, anyone have a technique for this or is it just brute force?

Also, when I was mucking around with IJ4 I broke the little piece of black plastic which covers the back (wire-side) of the connector. Anyone have a source for this stuff?

Now, the reason I wanted to get into the game adjustments was so that I could turn the background sound on. My game has the galloping horse sound and the various sounds when you hit the targets but it seems like there should be more than this. The machine on the PAPA gameplay video (http://pinball.org/videos/gameplay-videos/black-knight/), for example, produces quite a few more sounds than mine.

So I tried turning the background sound on at function 39 but no change (it may have already been on). Then I tried the sound test in diagnostics: sounds are produced for "02", "03" and "04" but I have no sounds for "00" and "01". Also, when I press the sound test button on the sound board itself, there's a couple of sounds that I've never heard while playing the game.....Where can we go from here?

Thanks, SV.