I just put together my optical compressor kit and it won't do a thing. Guitar signal will not pass through the pedal whether it is switched on or not. This is my 3rd build; I previously did a beaver and a mouse and they work fine. I'm using a power supply known to be good and a battery, so the problem is definitely in the pedal.
I may have installed the LED backwards - the directions did not indicate which polarity to put it in, so I followed the directions from my Mouse build (long lead in round pad) but I don't understand why this would cause any problems with anything else
Here are some pictures if anybody can help me spot the problem:

