It looks like Vss is not connected in the picture. There doesn't appear to be a jumper in the hole above the pin on the display board. That's due to what I mentioned about parallax and the reason for the recommendation to use a long lens.
Even before doing any initialization, the OP should be seeing rows of black squares if the power is ok and the the contrast is good.I wish I had thought of that.
Ok, you caught me. I didn't read it all carefully, I see now where you mentioned the boxes and contrast.