Greg,
I can't speak to the assembly language programming in the DOG EPROMS, but that U-shaped spanner wrench (above the allen) is used to tighten the cylindrical nut above it to the dial on the other side of the panel. The allen wrench tightens the knob to the shaft of the pot. I don't remember how the pot was tightened to the panel - maybe under the dial.
I also don't remember if a double giraffe was used at the end of Stairway, but the lumia effects were pretty much left to the Laserists. I almost always ignored Laser Images' advice on what to use and rather used what I thought looked best. No belt drives. All lumia motors were direct-drive. The fast ones had no gearbox. We used VERY expensive Swiss gearmotors (I think they were about $80 each and that was back in the 70's and 80's!) I have a few here if you want me to take a photo. I have pretty much all my optics (scan glasses and wheels) as well. They were very hard to get from LII and if I was ever rehired, I wanted my same stuff, so I kept it all.
Ron