Hi David,
Ah sorry, I see the wavelengths I posted (and listed by ISIS in the reports) are the values calculated from the fit, not the true values.
There does not seem to be a problem with the quality of the fit to the lines, at least within the range of lines used. (RMS ~0.2-0.3A seems typical for the ALPY.) The issue is apparent systematic differences in wavelength up to 3A between the lamp and the star)
Cheers
Robin