unable to "compare" more than 2 spectra

[ethanbass]

The comparison feature is not allowing me to load more than one additional spectrum on top of the spectrum I am viewing. If I attempt to compare more than one spectrum, they will show up under the comparisons tab but not on the graph itself. Also, when you roll over the graph, the label for the spectrum is "undefined" (see image below).

When I saved all of these spectra as a set, they all show up, but only some of them have the correct calibration. The distinguishing factor here is whether the spectrum was "saved with selected calibration" at the time of capture. If it was saved with selected calibration the calibration will not show up in the set, but if the calibration is copied from a reference spectrum after the time of capture then it will show up with the proper calibration. By re-calibrating spectrum 71375 I was able to move the spectrum into alignment with spectra 71372 and 71373 in set 3168.