That's an understatement. Haha The docs are basically worthless. There is so many different versions, all scattered around the web. Not to mention, most of them are in the form of a .pdf that is hundreds of pages, with a terrible search function. hah
With that said, Palette  is an awesome company that builds exactly what you are describing. I've used there products for a bit now for PS work, and love it!
Also, you generally don't want potentiometers for these applications, but rotary encoders. Pots = physical min and max position; encoders = infinite rotation. So for example, when you're switching from one photo to the next, pots would annoyingly keep the old value, while encoders will switch to the correct value. Just a little detail, but it's nice to have to right term to search for.
I don't know what it's like now, but I'm glad I don't use Photoshop anymore to worry about it