Yes, that is Bach's “Toccata and fugue in D minor” sitting on the music stand, imported from Germany and supposedly the closest version to the original that was available. I spent ages learning to play it (all the more harder because I was never taught the bass clef, and my organ doesn't have a double-octave pedalboard), could finally do it all from memory, then seemed to lose the ability to play it without tangling my fingers in knots. I might add that it's the very devil to play and read the music at the same speed that you play it at. And I don't know how anybody could count and play at the same time (it's nearly all sixteenths notes), not that I can count and play at the same time, anyway.
I've had a few people insist that you have to count while you play. But you don't sing that way, you do each note for what seems like the right amount of time instinctively. After explaining that to someone (how you sing notes for the right length), I took all the mystery out of playing for them, and they no-longer thought I was doing something difficult (damn, never reveal the tricks of the trade… damn, I've done it again).
The following pages have close-ups of different parts of the console, starting just left of the lower manual, and going around clockwise.