The documentation for the new app leaves a LOT to be desired. I submitted multiple examples where it was incomplete or wrong a month ago. None of it appears corrected or clarified.
Apparently, according to support, "An import will include only modified records since the previous run." So apparently there's an implied but never actually documented "Last Modified Date >= Last Successful Upload AND" added to the beginning of the SOQL, similar to how the legacy integration operated. Any other filter clauses that your imports had can be added as text as they were previously.
For the part " SFDC APP Filter for Last modified date on Imports", automatically added 'behind the scenes'. the filter was removed from the entry text box as it's a required element of any import. When an import runs, it does so using the filter just as an auto-sync does.
If you want to dig out more SOQL, please refer to the following guide:
the filter was removed from the entry text box as it's a required element of any import.
Wouldn't it be more helpful to document that somewhere other than a random thread on Topliners? I couldn't find any mention of it anywhere when I went looking a month ago.
Actually, we have the KB document, it is in the progress to publish. You will see the document soon.