It sounds here like this is something Nate might already be aware of and possibly working on: Current recommended SilverFast settings? - #6 by nate
He mentioned:
I’m trying to find a better way to do this… the Tiff Scan Prep utility is not ideal and there are just too many caveats to it. I’m working on a method that could avoid this, and that could make for a better workflow for those wanting the IR dust removal embedded into their Silverfast scans.