Ok, I have been researching this problem between work breaks

The LED in the back light does use R7 as the current limiter. I measured R7 as 3 ohms and verified with the markings. My R7 has been cooked pretty good but it still has good markings.
I measured across the LED - 2.06v @ 76ma.
My LED is not very bright at 3 volts, I suspect that its cooked too. I supplied 5v to the back light pins (15,16) and the current was about 800 ma! no wonder the printrboard was having issues.
I going to swap out the 3 ohm resistor.
And according to the data sheet (as lwalkera pointed out) the chip set can handle 5v with no problem.
Now I hope my Printrboard works with the LCD attached, the firmware I use now works great without the LCD but I never could get it to work with it. But with a 800ma draw on the power supply I suspect that the voltage regulator couldn't handle the load. The LM2841 buck voltage regulator used is optimized for 300ma with a typical draw of 525ma and a max of 900ma. Can we say overheating?
I have included some tasty pics.
EDIT: I used a 22 ohm 1/4w resistor and it works but its not as bright as before

If you remove R7 and place your resistor at R8 the back light power would be supplied from pin 2 (VDD), then only need 1 power wire
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