Hi avirmond ,
The two issues are unrelated. Yes, you will see messages related to Hg because the NIST610 file that comes with iolite does not include Hg (you could add it, or create another 610 RM file that includes it). Hg is not included in the GeoReM preferred values for 610 last I checked.
You are not getting propagated error for trace elements data because that is something we normally only calculate for U-Pb (or other isotope systems). If you're exporting a combined TE/U-Pb dataset, I would recommend exporting propagated error with the internal fallback. That way you'll get the propagated error for the U-Pb data and the internal error for TE data.
Also, regarding your follow up email where you asked about things being below LOD/LOD being infinite, that is because the dwell times are not set for that session/are 0. The Pettke LOD calculation has dwell time in the denominator so a dwell time of 0 equates to an LOD of infinity. I believe dwell times can be automatically imported from a .FIN file accompanying the .FIN2 file, but if that file is unavailable or there is more than 1 .FIN file in the same folder you won't get the dwell times automatically and need to specify them in the Tools->Dwell Times dialog.
All the best,