12864ZW - Not working

Thank you thank you thank you!!

I managed to get a u8glib Hello World example working, both in 8 bit and serial mode by uncommenting the U8GLIB_ST7920_128X64_1X line.

The problem I have now is the "Hello World" text is barely visible, and only when held very flat. I'm wondering if the jumpers can be changed so I can use a variable resistor to change the contrast, I don't know if anyone has had any luck with that?

The attached photo shows J1 is disconnected which explains why contrast wasn't changing. I'm thinking of connecting it, but I don't know if that could damage the unit? Also R12 is missing so Vout is also disconnected.

EDIT: Contrast is now fixed as well! I soldered J1. This resulted in V0 floating to 7.5v. So all I had to do was attached a variable resistor between V0 and Vdd. (The third pin of the variable resistor wasn't needed.) The VR I used was 10k ohm.

Thank you for your help, Don, Oliver, Bajdi!