Also, this sketch has pin 3 setup as the backlight on the shield. This way you have PWM control over the backlight. You can accomplish this by cutting the VCC trace and soldering the PIN3 jumper on the back of the shield. You can read more on how to do that here.
This sketch has EEPROM settings, if you have not used them before, the values will be zero and need to be set. There are notes about this in the sketch on lines 92 & 93.
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