I am currently in the process of recatalogging my collection on numista to replace a spreadsheet, and am using my own ID numbers for each entry, but on numista I cannot search or sort my collection by this field. The ability to sort by this and other fields that you are currently unable to would be a great addition, and it would benefit all the same people as adding these newer fields did.
Sorting or searching by internal ID would be a spectacular addition to numista. I personally have over 800 coins with unique internal IDs.
Could be as simple as prefix searching the catalog so instead of searching “123456” as the internal id the search term would be “IID 123456” or something similar. maybe (123456) for iternal IDs.
The export is sorted on several fields, if you change this sorting, to restore it you must either have noted it, made a copy of the file, or inserted an additional column for the original row numbers.