Its hard to tell, but where is your 5v in going to the "optoIn" Cant really see it. One other thing, the underside of that board is covered in solder flux! You really need to clean that off really well. I use some electronics cleaner you get at radio shack. It comes in a aerosol can, with a bristle brush on the top. Just use that brush to gently scrub the entire board, while spraying out the solution through the brush. Then rinse the board with a gentle stream of warm water. Dry it off VERY well before powering up the board!! I use an air blow gun with low pressure to get all the water off, then let it sit for a few hours. You can also use that electronics duster stuff in cans as well. Just be sure to get all the small pin holes of the processor socket, and the db9 and db37 pins clear of water. You will want to remove the processor before you clean it though. Everything else can get soaked with water, it wont hurt it. If you still see a white haze on the board after cleaning, you didnt get all the flux residue off, so go over it again in the same procedure. Excessive flux residue can create very small shorts and all kinds of issues, so get it cleaned off.