The fork adjuster operates like the high speed adjuster on the recent KYB/Showa shocks. If you look closely, you will see a square drive on the bottom of the adjuster that will preload a spring which acts on the bottom of the valve stack. In the softest setting, it doesn't touch the shim stack at all, but as you wind it in (stiffer), it eventually touches the stack and effectively changes the diameter of the clamping shim (to a point). The lowspeed adjuster works like a traditional adjuster in that it closes off the bleed hole as it's turned in.
As delivered, the fork adjuster requires the stock piston, check plate, etc.. You can use the stock valve stack, but they recommend a re-vavle as the valve stack build is critical to performance. The main feature of the device is that it allows you to add some highspeed valving without taking the fork apart, not that it provides the best ride quality. That would come from the re-valving part. One thing just occured to me....this could be a problem with multi-stage valvestacks. As you add high speed adjustment to the fork, it will push on the "highspeed" stack, possibly closing the cross over between the stacks. Regardless, I think this has a lot more potential than the Delta Valve from R.T. (which doesn't even utilize a piston & valve stack).
I haven't worked with the shock adjuster but it appears to work like the recent KYB and Showa high speed adjusters. The picture I saw had basically the same components to it, but there could be small differences in the design.