The issue with the wrong time stamp in NMS, after editing a save file, does not happen with NomNom. The collection of images below shows SE on the left and NomNom on the right. SE changes the modified time but not Created time. NomNom appears to save as "brand new" files. I tried copying the binary contents of the SE edited save and mf_save files into "new" files. It sort of worked in the sense that the Created time of the new save file was shown in the NMS save selection window. However, I think it opened the Automatic save, suggesting something may have gotten corrupted. I'll check later. My very lay opinion is: something is being left out or added to one or both of the files (save and mf_save). Not very helpful, but perhaps something.
Minor update. If a save is opened with SE and Edit Raw JSON is chosen, and the JSON editor closed without any changes being made, then saving the file results in the timestamp error issue. Like NMS, NomNom shows this newly saved file with the old Created timestamp, and not the new Modified timestamp. If the save is opened and closed with the Edit JSON feature in NomNom, then saved, the timestamps are all the same and up-to-date as shown in the image above.
The issue with the wrong time stamp in NMS, after editing a save file, does not happen with NomNom. The collection of images below shows SE on the left and NomNom on the right. SE changes the modified time but not Created time. NomNom appears to save as "brand new" files. I tried copying the binary contents of the SE edited save and mf_save files into "new" files. It sort of worked in the sense that the Created time of the new save file was shown in the NMS save selection window. However, I think it opened the Automatic save, suggesting something may have gotten corrupted. I'll check later. My very lay opinion is: something is being left out or added to one or both of the files (save and mf_save). Not very helpful, but perhaps something.