Hi!
I have just finished step 12 and I think I did everything right.
The problem is that my screen does not light up every time i flip the switch. Sometimes i find sweet spot wher it works everytime (comepletly normal, it says adjust contrast),but if i move it and try turning the screen on it isnt working.
I tried resoldering batery and checked everything 3 times.
Your image is a little bit blurry so I’m guessing that the blue marked solder joints are looking like shortened (connection bewteen two or more solder joints) and the green marked solder joint looks like there is almost no solder so please resolder those joints