If it helps anything...
I am running an iDuino with a blue backlight display, too. In the code, you can change the contrast settings, and upload it again. I am using a contrast of 315. You can change those numbers (and any others you would want to change) in the code towards the top. Where it says:
Code:
char * parmLabels[]={"Contrast","VSS Pulses/Mile", "MicroSec/Gallon","Pulses/2 revs","Timout(microSec)","Tank Gal * 1000","Injector DelayuS","Weight (lbs)","scratchpad(odo?)"};
//unsigned long parms[]={15ul,16408ul,684968626ul,3ul,420000000ul,13300ul,500ul};//default values
unsigned long parms[]={95ul,8208ul,500000000ul,3ul,420000000ul,10300ul,500ul,2400ul,0ul};//default values
You can change the 95 to 315 (or other numbers) and see how things work. I just changed the "hundreds" number, and there were lots of settings that worked, and lots that looked pretty bad, so you may have to try a few to find a good one. You can check out
how I did my build (and see any potential differences between our builds). I am still working on it, but it's coming along nicely.