pic: Banana for scale

[GeeTwo]

That's only 11 buttons; one of our early UI designs had about that many. We eventually simplified so we can get it on an xBox controller.

My guess (not that I think I'm right, but just making the point that you can use this many buttons) is that the five white buttons are for lift levels, the big red is cancel or all stop, lower right is "score" (lower the lift until it disengages, possibly sensed by current draw), lower left black is pick up a tote, top black is pick up an RC, and the greens are to place those pieces atop a tote, and maybe pick up the bigger stack.