I have tried my best to make a precision rectifier on my own, although it's like 15-20 years ago I last used my soldering iron (bought the module ready-assembled from dmitri...)
Sadly I have a constant high input on the SnareH, so something went wrong - but what? I know the soldering points don't look really good (cuz of my okd iron I guess) but I tried my best and believe I understood the schematiccs and followed them, and as far as I measured it there are no shorts.
I attached some pictures of my board and hope it helps... I mirrored the image of the bottom so you can easily compare to the upper side.