Hi Chris - Thanks for offering this help... I think (I think!) the peaks are labeled correctly. Perhaps you could take a quick look at the images in this album and see if you agree? I do notice that the amount% is 0.000. I haven't found anywhere to enter that information (I'm using urea for the calibration, so I do know the C:N). I did notice in the IRMS method, one could possibly enter the info (final screenshot). I cannot find much on that setting (yet) in manuals, but it seems it would be restrictive running unkowns... I have tried to change the end of the N window because it labels the peak as N only seconds before it needs to calculate the dilution. I thought it might be a timing issue, but for the C peak, the area is calculated well before the C peak comes to the Conflo, so I nominally ruled that out... Thanks again for offering help! 

-Tom