Not much documentation, but doesn't really need much. The only cause for pause was which way 'round to place the R2R networks -- the board has pin 1 marked, but the ladder networks don't. Tip: the resistance between pin 1 and pin 2 is 20KΩ. If you get 40KΩ then you are metering between pin 9 and 10 -- turn it around!.
Product works as designed, my only recommendation for improvement would be breakouts for the lamp voltage and C-field pins for monitoring, and widening the board slightly so it could be screwed to the standoffs on the LPRO-101 would be nice.
Nice and clean way to work with R2r, I made a circuit on my breadboard, but the BNC jacks were hard to keep on the breadboard. This was great for being able to just put on the Arduino and the BNCs were stable, and easy to work with. It did not come with documentation, but really I am not sure it needs it, if you know you want an R2r circuit, then its there. I bought as the kit, took 10 mins to solder it together. I used his code, and then changed it to write my name on my scope, worked great.